V     ^     Mr 


0^2 


t-**- 


%m 


■^'^M 


K^.*\Mi/^ 


i.y 


<>S.     .  V 


UNIVERSITY  OF  ILLINOIS 
LIBRARY 


Class 


Book 


Volume 


■i^^ 

-^^ 


•4:^^- 


,r<r.  hi  \' 


'Ai^^ 


"t,  <••■/.  ■ 


v'a  V-  r 


The  person  charging  this  material  is  re- 
sponsible for  its  return  to  the  library  from 
which  it  was  withdrawn  on  or  before  the 
Latest  Date  stamped  below. 

Theff,  mutilation,  and  underlining  of  books 
are  reasons  for  disciplinary  action  and  may 
result  in  dismissal  from  the  University. 

UNIVERSITY    OF     ILLINOIS     LIBRARY    AT    URBANA-CHAMPAIGN 


fPB     91976 

«  16  t976 


UNIVERSITY  OF  ILLINOIS  BULLETIN 


Vol.  V.  AUGUST.  17,  1908  No.  39a 

[Entered  February  14.  1902,  at  Urbana,  Illinois,  as  second-class  matter 
under  Act  of  Congress  of  July  16th,  1894. 


BULLETIN  No.  7.    DEPARTMENT  OF  CERAMICS 

C.    W.    ROLFE,    Director 


THE  INFLUENCE  OF  FLUXES  AND  NON-FLUXES  UPON 

THE  CHANGE  IN  THE  POROSITY  AND  THE 

SPECIFIC  GRAVITY   OF   SOME   CLAYS. 


By  A.  V.  BLEININGER  and  J.  K.  MOORE 


I  907  -  I  908 


PUBLISHED   FORTNIGHTLY   BV  THE   UNIVERSITY 


THE  INFLUENCE  OF  FLUXES  AND  NON-FLUXES  UPON 

THE  CHANGE  IN  THE  POROSITY  AND  THE 

SPECIFIC  GRAVITY  OF  SOME  CLAYS. 

BY 

A.  \'.  Hli:i.\in(;i:u  and  J.  K.  Mooin:.  Chainpaifiii,   IIL 

\'itTitication  may  be  said  to  be  ])artial  fusion.  Wlion 
speakiiij;  of  clays  the  pronrcss  of  vitriticatiou  is  iM]uivaleiit 
to  pro«»Tessive,  partial  fusiou  of  the  various  luincral  coii- 
stitiiciits,  «>ov(tii(m1  by  the  iiiiiiei-al  constitution  of  the  body 
as  a  whole,  the  size  of  urain  and  the  strucrure  of  the  ware 
for  which  the  clay  is  employed.  ('om])lete  vitriticatiou 
ensues  when  enough  (day  has  been  used  to  till  u])  the  ])ores 
oi'iiiinally  pi-esent.  Fi'om  the  ])ractical  stand])oint  this  is 
indicated  by  the  fact  that  but  little  water  is  absorbed  by 
the  (day  on  immersion.  Without  lioin.u  fully  into  the  de- 
tails of  the  process  it  may  be  said  that  the  ])henomena  of 
fusion  accomi)any  the  vitrificatioii  of  clays. 

Fusion  considered  from  the  .ucneral  siandi)oint  of  sili- 
cates is  sharply  defined  only  for  some  definite  minerals; 
even  in  many  silicates  it  is  a  more  or  less  gradual  transi- 
tion from  the  solid  to  the  semi-liquid  or  li(iuid  condition, 
and  therefore,  in  a  hetero_u-en(M^us  rock,  like  (day,  even 
thou|L»:h  all  of  its  constituents  were  reduced  to  uniform, 
extreme  fineness,  fusion  must,  in  the  nature  of  the  cas(\ 
cover  a  considerable  tem])erature  interval. 

From  tlie  practical  standpoint,  tln^refore,  vitrification 
may  be  followc^d  by  determininu  the  i)orosities  at  dilferent 
temperarures.  just  as  Prof.  Purdy  has  done  in  his  valuable 
contribution  in  Vol.  IX  of  the  Transactions  of  this  Society. 

In  addition,  two  ])henomena  of  fusion  demand  our  at- 
tention. Tliese  are  (losely  r(dated  and  are:  ('han.iie  in 
molecular  voluuu'  and  transference  of  heat.  In  nearly  all 
silicates   the   volume   is   increased   on    fusion   or,   ij)   other 


4        THE  INFLUENCE  OF  FLUXES  AND  NON-FLUXES  UPON  THE  CHANGE 

words,  the  density  is  decreased.  Tliis  iucrease  in  volume 
is  intimately  connected  with  the  fact  that  the  amorphous 
or  fused  condition  represents  a  greater  energy  potential 
than  the  crystalline  state.  AVe  find,  as  a  rule,  that  the 
amorphous  modification  of  a  substance  is  more  soluble  and 
capable  of  stronger  reaction  than  the  anisotropic  form. 
That  fusion  results  in  an  increased  volume  has  been  deter- 
mined frequently,  and  in  a  few  cases  it  was  even  possible 
to  establish  this  fact  for  minerals  in  the  fused,  liquid  con- 
dition. Thus  Doelter  found  the  specific  gravity  of  crys- 
talline augite  to  be  3.3,  that  of  the  hot,  liquid  mass  2.92, 
and  of  the  solidified  glass,  2.02.  The  so-called  coefficient  of 
crystallization,  in  fact,  is  determined  by  the  specific  gravity 
of  an  intermediate  stage  compared  with  the  specific  gravity 
of  the  crystal.  If  dx=specific  gravity  at  any  stage  and 
dc^specific  gravity  of  the  crystal,  dx-^dc==coefficient  of 
crystallization.  E.  V.  Fedorow  has  shown  that  this  agrees 
with  the  facts. 

With  reference  to  the  heat  of  fusion  we  can  say  that 
this  is  of  constant  magnitude,  and  is  equal  to  about  100 
gram  calories  per  gram.  Fusion  is  always  accompanied 
by  absorption  of  heat.  This  is  a  necessary  conclusion,  for 
in  fusion,  work  is  always  done  against  the  external  pres 
sure  and  the  cohesion  of  the  particles,  both  of  which  tend 
to  oppose  the  increase  in  volume.  That  the  non-crystalline 
condition  corresponds  to  a  higher  level  of  energy  may  be 
indirectly  shown  by  experiments  such  as  the  determination 
of  the  heat  of  solution.  Thus  1  gram  of  crystalline  sodium 
silicate  evolves  457  calories,  while  the  same  amorphous 
substance  gives  off  486  calories.  Similarly,  crystalline 
leucite  sliows  507,  the  amorphous  substance  533  calories. 

From  what  has  been  said  it  follows  that  crystallization 
shows  the  opposite  characteristics.  On  crystallization  the 
volume  decreases  and  heat  is  given  off,  thus  r(?tarding  the 
cooling  of  the  mass. 

The  fact  that  clay  bodies  decrease  in  density  on  vitrifi- 
cation had  been  realized  quite  early  by  Laurent,  Krong- 
niart  and  Rose,  and  during  the  last  decade  has  been  used 


IN    THE    POROSITY    AND    THE    SPECIFIC    GRAVITY    OP    SOME    CLAYS.  5 

ill  very  exact  work  by  Day  and  Shepherd,  Mellor  and  oth- 
ers. The  rate  of  change  in  specific  gravity  and  porosity 
lias  been  enipb)ved  in  the  ])lotting  of  density  and  porosity 
curves  by  Berdel  in  his  excellent  and  extensive  work  on 
white  ware  bodies  and,  later,  by  Purdy  in  his  work  already 
cited.  Piirdy  eni]th;»sizes  the  rate  of  chan^'e  in  porosity 
and  makes  use  of  the  specific  gravity  only  for  the  purpose 
of  determining  the  porosity  which  he  considers  as  the  cri- 
terion for  judging  the  ])rogress  of  vitrification,  lie  calcu- 
lates the  porosity,  expressed  in  per  cent,  frtmi  cla^^  brick- 
ettes  burnt  at  different  temperatui'es  and  uses  the  formula: 


%  h:^s)'»«. 


where  %  P^per  cent  porosity, 
W=wet  weight  of  brickette. 
D=dry  weight. 
S=suspended  weight. 

The  wet  weight  corresponds  to  the  weight  of  the 
brickette  after  immersion  in  water,  in  vacuo. 

By  plotting  the  porosities  of  a  clay  at  different  tem- 
peratures he  obtains  a  curve  which  un«inestionably  indi- 
cates the  progress  and  rate  of  vitrification.  Prof.  Purdy 
advocates  the  use  of  such  curves  in  clay  testing  for  the 
purpose  of  determining  the  character  of  a  clay,  and  there 
is  no  doubt  but  that  this  offers  a  very  convenient  and 
valuable  method  of  testing  which  deserves  general  applica- 
tion. The  writers  make  continuous  use  of  the  method  in 
carrying  on  clay  tests. 

While  the  porosity  curve  is  of  great  practical  value, 
yet  it  seems  to  the  writ<M's  that  mnch  information  in  regard 
to  the  mechanism  of  the  changes  occurring  in  clay  during 
burning  is  obtained  from  the  ])articnlar  study  of  th;^ 
changes  in  s])ecific  gravity,  that  is,  the  s])ecific  gravity 
curves.  In  using  this  method  we  ai'e  sim])ly  adopting  the 
means  employed  by  many  investigators  in  following  chemi- 


D         THE  INFLUENCE  OF  FLLXES  AND  NON  FLUXES  UPON  THE  CHANGE 

cal  trau.sformatiou,  as,  for  instance,  by  Van't  Hoff  in  his 
study  of  plasters,  etc. 

While  in  many  clays  and  clay  bodies  the  porosity  and 
specific  gravity  curves  are  practically  parallel,  yet  it  may 
happen  that  certain  changes  occur  which  are  indicated  onl\ 
by  the  specific  gravity  curve. 

In  discussing  the  density  of  clays  we  must  clearly  dis- 
tinguish two  values  of  the  density  which  differ  according 
to  the  method  by  which  the  work  is  carried  out.  If  we  take 
a  brickette,  weigh  it  when  dry,  immerse  it  in  water,  in 
vacuo,  and  again  weigh  it  suspended  in  water,  we  obtain 
by  calculation  from  the  simple  formula  : 

Dry  weight  in  air 
Specific  gravity= 


Dry  weight  in  air — suspended  weight, 

the  specific  gravity  of  the  brickette  as  a  whole,  including 
the  effect  of  enclosed  pores  and  other  cavities.  On  the 
other  hand,  by  crushing  and  powdering  the  brickette  and 
using  the  pycnometer,  being  careful  to  exhaust  the  air  from 
the  powdered  material  and  water  in  the  apparatus,  we 
shall  have  the  specific  gravity  of  the  burnt  clay  itself,  the 
effect  of  the  pores  and  cavities  having  been  eliminated. 

In  addition  to  the  change  in  volume  brought  about  by 
fusion  we  have  other  voluiue  transformations  caused  by 
so-called  inversions,  that  is,  the  character  of  the  molecular 
arrangement  of  many  compounds  suffers  an  alteration. 
The  best  known  instance  of  this  kind  of  transformation  is 
the  change  of  quartz  into  tridymite.  On  filling  a  crucible 
with  pulverized  cpiartz  and  heating  it  this  change  is  mani- 
fested quite  strikingly  by  the  bursting  of  the  vessel  due  to 
the  increase  in  volume  incident  to  this  molecular  change. 
This  inversion 

quartz  "^    tridymite 

occurs  at  about  800° C.  Similarly  it  is  found  that  fused 
quartz  which  necessarily  is  in  the  amorphous  condition 
is  transformed  to  tridymite,  which  is  shown  by  the  dim- 


IN    THE    POROSITY    AND    THE    SPECIFIC    C;RA\  I  IV    OF    SOME    CI.AYS.  I 

iiiiii^  of  tilt'  iihiss.  Since  this  cliaiiiie  is  rcvcrsihle  it  follows 
that  below  800^  the  tridvinite  reverts  to  quartz.  This  latter 
fhantce  is  rather  slu,a2:ish  and  requires  <onsi(l(M*able  time, 
we  can  say,  therefoi'e,  that  ([uartz  never  crvstallizes  from 
mineral  fusions  exeeptinc;  in  the  presence  of  catalyzers. 
(Quartz*  then,  is  the  unstable  foini  of  silica  from  800'  up- 
ward, and  it  will  chanjic  to  tridymite  whenever  oi)por- 
tunity  olfers.  We  have  thus  a  volume  change  which  on 
heatiiiii'  a  clay  is  shown  by  the  decrease  in  density.  Puri- 
fied natural  (juartz  has  a  s])ecitic  «»ravity  of  2.654  (25^), 
while  tridymite  ])repare<l  from  (]uartz  has  a  density  of 
2.o2(>;  when  i>rei)ared  from  fused  (|uarrz  its  density  is 
2.0I8.  The  density  of  quartz  lilass  was  found  to  be  2.213. 
On  coolinj;  a  clay  any  chanjie  from  tridymite  to  quartz 
stands  for  an  increase  in  density,  as  must  be  evident  from 
the  above  figures. 

Similar  inversions  are  known  for  meta  and  ortho  cal- 
cium silicate.  Thus  we  have  the  pseudo-hexajional  nu^ta- 
silicate  and  wollastonite  and  three  forms  of  the  ortho 
calcium  silicate.  These  are  the  al])ha,  beta  and  gamma 
modifications  whose  densities  are  3.27,  4.28,  and  2.07,  re- 
spectively. There  are  doubtless  other  inversions  which  are 
not  yet  known  to  us. 

Still  another  source  of  volume  chanjies  is  to  be  souiiht 
in  chemical  reactions  takinii'  place  in  clay,  such  as  the 
exothermic  reaction  takinji'  place  in  clay  substance  at  about 
1000,  in  which  evidently  an  isomeric  compound  differinji' 
from  the  ])revious  com])Osition  in  structure  is  formed. 
Other  examples  are  the  chanei?  of  calcium  carbonate  to  the 
oxide,  the  interaction  of  lime  and  iron  oxide,  the  formation 
(»f  <-ertain  lime  silicates  above  1200^,  the  formation  of 
.spinels,  majiuetic  oxide,  etc.  There  must  be  many  chemical 
i-eactions  which  at  present  are  entirely  unknown  to  us. 

In  studyinji;  the  changes  in  the  two  specific  jiravities, 
then,  we  miiiht  be  able  to  summarize  the  causes  of  the 
volume  changes  as  follows: 

*Day  and  Shepherd.     Jnur.  Am.  Clicm.  Sec.  \'('\.  28,  p.  1099. 


8  THE    INKLLENCK    OF    FLUXES    AND    NON-FIAXES    IPON    THE    CHANGE 

A.  Apparent  specific  gravity.         B.  True  specific  gravity. 

1.  Inversion  1.     Inversion 

2.  Fusion                           •  2.     Fusion 

3.  Clieniical  reactions  3.     Chemical  reactions 

4.  Pore  space  4.     Crystallization 

5.  Formation  of  "blebs" 

6.  Crvstallization. 


A  slight  change  common  to  both  forms  of  specific 
gravity  is  that  caused  by  the  differences  in  the  coefficient 
of  expansion  between  the  fused  and  crystalline  portions. 
We  observe,  lience„  that  the  apparent  specific  gravity  must 
be  the  algebraic  sum  of  at  least  six  and  thee  true  specific 
gravity  of  four  factors. 

On  lieatiug  a  clay  body  the  changes  taking  place  in 
quartz  and  feldspar  and  perhaps  in  clay  substance,  the 
character  of  which  has  been  discussed  before,  tend  to  in- 
crease tlie  volume  or  to  decrease  the  density.  We  might 
say,  therefore,  that,  in  terms  of  tlie  density,  the  change  is — 
in  character.  On  cooling  the  clay,  however,  during  the 
critical  temperature  intervals  of  each  constituent  inversed, 
the  density  change  is-ffor  then  the  inversion,  as  far  as 
reversible,  proceeds  the  other  way.  But  since  the  cooling 
nearly  always  takes  place  far  more  rapidly  than  the  heat- 
ing up,  it  is  quite  probable  that  this  change  in  volume  is 
but  slight. 

We  already  know  that  the  volume  is  increased  on 
fusion  and  remains  increased  unless  crysrallizatiqu  takes 
place  on  cooling.  The  change  in  density  on  fusion,  hence, 
is — as  far  as  most  silicates  are  concerned. 

Chemical  reactions  may  cause  either  -|-  or  —  changes, 
but  on  heating,  according  to  the  theorem  of  Le  Chatelier, 
the  changes  are  probably  —  in  sign,  as  a  rule. 

The  pore  space,  still  remaining  in  the  clay  which  has 
not  yet  been  closed  up  by  the  softened  or  fused  material 
of  course,  tends  to  decrease  the  apparent  density.  The 
same  thing  is  true  of  the  blebs  forniel  by  the  evolution  of 


IN    THE    I'OROSnV    AND     IHK    SPECIFIC-    GRAVITY    OF    SOME    CLAYS.  VI 

uasos  within  the  chiy.  This  formation  of  gas  is  a  vorv 
important  factor  in  the  meclianical  strenoth  developed  in 
a  elav,  and  this  fact  has  been  brought  out  very  clearly  by 
Purdy.  In  some  clays  the  porosity  thus  contributed  may 
be  coincident  with  vitrilication  and  hence,  althoujih  the 
clay  itself  may  be  perfectly  vitrified,  the  porosity  curve 
would,  in  such  a  case,  fail  to  indicate  vitrification.  Several 
such  clays  and  bodies  have  been  observed  by  the  writers. 

Crystallization  would,  in  the  nature  of  the  case,  take 
place  only  when  the  temperature  has  ceased  to  rise,  that  is. 
when  the  kiln  is  "soakin<»,"'  the  tenii)eratnre  just  holding 
its  own  or  wlien  coolino-  begins. 

That  crystallization  does  take  i)lace  to  some  extent  in 
clays  is  established  beyond  a  doul)t.  The  senior  writer  in 
examining  a  section  of  paving  brick  which  happened  to 
show  two  well  defined  ar^as  of  properly  burnt  and  over- 
burnt  clay,  found  numerous  crystals,  neefUe-like  in  shape, 
in  the  over-burnt  portion,  but  no  evidence  of  crystallization 
in  the  sound  part.  AVegemann,  in  collaboi-ation  with  Prof. 
Purdy,  found  considerable  crystallization  in  over-burnt 
])aving  brick,  fine  needle-like  crystals,  yellowish-green  in 
color,  of  unknown  composition  as  well  as  minute  crystals 
of  iron  oxide.  Crystallization,  as  we  know,  stands  for 
decrease  in  volume  or  increase  in  density,  and  hence  wo 
may  say  that  it  is  a  +  change,  in  terms  of  the  density. 

The  investigation  which  is  the  basis  of  this  paper  was 
cai'ried  on  for  the  purpose  of  determining  tlie  character  of 
the  changes  in  the  density  and  porosity  of  clay  bodies  to 
which  various  reagents  have  been  added,  burnt  at  different 
temperatures,  and  it  is  due  Prof.  Purdy  to  say  that  it  was 
inspired  by  his  paper  on  the  pyrochemical  and  physical 
changes  of  clays.  It  was  proposed  to  broaden  the  scope  of 
the  work  and  to  determine,  if  possible,  the  following 
(juestions: 

1.  To  what  extent  do  tlie  apparent  specific  gravity 
and  porosity  curves  agree  in  indicating  vitrification  in  the 
study  of  various  additions  to  clays? 

2.  If  there  are  anv  deviations  where  and  liow  do  thev 


10  THE    INFLUENCE    OF    FLUXES    AND    NON-FLUXES    UPON    THE    CHANGE 

occur,  and  ^\hat  is  their  character?  Are  there  aii}'  maxi- 
mum or  minimum  points? 

3.  Under  what  conditions  are  certain  substances 
fluxes,  and  when  are  they  non-fluxes  or  refractories? 

4.  At  what  rate  do  these  substances  either  accelerate 
or  retard  fusion? 

5.  At  what  temperatures  does  the  fluxing  or  refrac- 
tory character  of  certain  additions  begin? 

6.  What  are  the  areas  enclosed  by  some  isotliermals'.' 
In  the  work  of  Purdy  the  specific  gravity  and  porosity 

curves  agree  quite  well  in  indicating  vitrification,  and 
hence  it  is  but  natural  to  inquire  whether  this  is  the  case 
under  all  conditions.  Any  deviations  might  be  reasonably 
ascribed  to  conditions  pointing  towards  certain  physical 
or  chemical  plienomena  peculiar  to  the  composition  stud- 
ied, since  we  know  that  the  density  changes  with  the  trans- 
formation caused  by  chemical  reactions,  solution  or  crys- 
tallization. 

The  term  flux  is  but  a  relative  one,  and  no  particular 
class  of  substances  can  be  designated  as  fluxes.  In  a  sili- 
cious  material  like  clay,  basic  substances  act  as  fluxes, 
while  in  basic  compositions  like  Portland  cement  silicious 
compounds  unquestionably  behave  as  such.  In  addition  we 
must  consider  the  fact  that  a  small  portion  of  any  sub- 
stance, no  matter  what  its  composition,  dissolved  in  an- 
other, will  lower  the  fusing  point,  provided  no  cliemical 
reaction  takes  place. 

The  rate  of  these  changes  is  of  interest  in  as  much  as 
this  factor  may  have  considerable  influence  upon  the  prac- 
tical application.  It  may  be  either  too  rapid  or  too  slug- 
gish. In  this  manner  we  can  establish  the  point  at  which 
no  further  change  is  observed  and  when  additional 
amounts  show  no  effect. 

The  question  of  temperature  establishes  the  points  at 
which  the  activity  of  the  various  additions  become  manifest 
and  at  what  temperature  the  maximum  effect  is  shown. 

The  areas  enclosed  by  successive  isothermal  curves  are 
designed  to  show  the  rate  at  Avhich  vitrification  progresses, 


IN    THE    POROSITY    AND    THE    SPECIFIC    GRAVITY    OF    SOME    CLAYS. 


U 


and  the  coiuiwsitiou  of  the  fusible  conibination  as  well  as 
the  chaiiiie  in  the  composition  on  raising  the  temperature. 
It  might  be  said  that  thus  the  changes  in  the  eutectic  com- 
binations are  indicated. 

The  clays  upon  which  the  effect  of  various  substances 
was  studied  were  as  follows : 

1.  Floi-ida  kaolin,  and  in  several  instances,  Georgia 
kaolin. 


I'all  clay,  Tennessee  Xo.  3. 
Shale  from  (lalesburg,  111. 
Shale  from  ( 'rawfordsville,  Ind, 
Shale  from  Canton,  Ohio. 
The  materials  added  to  the  above  claj'S  were  as  fol- 
lows : 


8. 
4. 


1 .  Feldspar 

2.  Whiting 

3.  Ferric  oxide 

4.  Flint 

5.  Florida  kaolin 


(I.  Feldsi)ar-flint 

7.  Whiting-tlint 

8.  Ferric  oxide-flint 

0.  Ferric  oxide-whiting 

10.  Cornish  stone 


The  composition  of  some  of  the  materials  are  given  in 
the  following  table: 


i     ■ 

Loss 

Mois- 

SiOo 

AljOa 

Fe»03 

FeO 

TiOi 

CaO 

MgO 

K.,0 

Na,0 

on  ig- 

ture 

<^<. 

■        1c 

% 

% 

% 

% 

% 

% 

9t 

nition. 

9fc 

Galesburg*  | 

Shale    ..■ 163.62 

Crawfordsville* 
Shale    '68.50 


16.31!    6.22'2.J 

16.98I  5.77I-- 


Canton* 
Shale 


III 

.\^l.l\\22.2\\    7.2(j\ 


0.96 


0.63 

0.99 

0.56 
0.30 


I--I4 
1. 71 

1.63 
O.II 


2. 6011.50 
2.97 


3.36 


Feldsp;ir    168.22:17.83! .  . 

Flint    igS.Oo! [ |.. 

I           I           I           I 
Inin    Oxido.  ...  I I l99-00[ I I I I 

Whiiin^-    !   1.62I3.50! | | 152.651 | 

*Pur(ly  and  Moore,  Trans.  Am.  Cer.  Soc,  Vol.  9 


12.13 


6.260.38 

7-mo-27 
8.00  .... 


1.90I0.35  .... 


I0.50 


12  THE    INFLUENCE    OF    FLUXES    AND    NON-FLUXES    UPON     THE    CHANGE 

Tlie  compositions  are  expressed  in  percentages 
throughout,  since  the  clianges  to  be  noted  are  shown  in  this 
manner  as  well  as  if  molecular  relations  had  been  em- 
ployed. In  fact,  considering  the  heterogeneous  character 
of  the  clays  used  and  their  physical  differences,  the  consid- 
eration of  chemical  formula  would  have  appeared  to  be 
almost  absurd.  This  is  especially  true  since  we  were  deal- 
ing only  with  the  vitrification  and  not  the  fusion  of  bodies, 
and  particularly  since  the  earlier  stages  of  vitrification 
were  of  special  interest  to  us. 

The  materials  were  weighed  out  in  the  dry  condition, 
and  usually  the  two  ends  of  a  series  were  ground  dry  in 
the  ball  mill  for  two  hours.  From  the  two  end  composi 
tions  the  intermediate  mixtures  v.ere  obtained  by  blending 
and  thorough  grinding  in  a  mortar.  Each  batch  was  then 
made  up  with  water  to  the  desired  consistency,  and  after 
thorough  wedging  was  molded  into  a  brickette  of  the  di- 
mensions :  12.8x7.8x1.3  cm.  in  a  brass  mold  provided  with 
a  movable  bottom.  Each  brickette  was  cut  up  into  eight 
prisms,  which  were  stamped  with  the  series  numbers.  After 
thorough  drying  one  brickette  from  each  mixture  was 
taken  and  placed  in  a  sagger.  Each  burn,  therefore,  con- 
tained one  of  the  eight  small  brickettes  of  exerj  composi- 
tion. Tlie  saggers  were  placed  and  cones  put  in  the  kiln, 
well  protected  from  any  direct  flame.  Th(B  kiln  used  was  a 
down-draft  test  kiln,  fired  with  coke,  and  has  been  de- 
scribed in  the  paper  on  "Fritted  Glazes"  by  R.  C.  Purdy 
and  H.  B.  Fox.*  The  firing  temperatures  wel'e  cones  09, 
06,  03,  01,  2,  4,  6;  some  brickettes  which  had  been  left  by 
Prof.  Purdy  as  part  of  an  unfinished  investigation  were 
fired  to  cones  9,  11,  and  13.  The  cooling  of  the  kiln  was 
hastened  in  no  case,  though  the  damper  was  left  open. 

The  brickettes  when  cold  were  freed  from  adhering 
particles,  weighed,  and  immersed  in  distilled  water  for  48 
hours;  they  were  then  boiled  for  one  hour  and  finally 
placed  in  a  large  suction  flask  connected  to  a  filter  pump 

*Trans.  Am.  Cer.  See,  Vol.  IX. 


IN    THE    POROSnV    AND     IHt    SI'KCIFIC    GRAVITY    OF    SOME    CLAYS.  18 

iiiul  left  there  until  uo  more  air  bubbles  were  given  off, 
which  usually  took  several  hours.  This  method  was  fouud 
to  be  more  satisfactory  than  exhaustion  by  an  air  pump,  as 
it  seemeil  to  result  in  better  absorption  of  water.  The 
brickettes  were  then  suspended  in  water  by  attaching  with 
a  silk  thread  to  the  beam  of  the  balance  and  thus  weighed. 
Immediately  afterwards  they  were  weighed  in  air,  thus 
giving  the  wet  weight.  The  specific  gravity  was  calculated 
by  the  usual  foimula  and  the  ])()rosity  by  the  Purdy  for- 
mula. 

Several  hundred  pycuometer  specific  gravity  determina- 
tions were  also  made  on  the  dried  and  pulverized  brickettes 
by  weighing  a  quantity  of  the  powder  in  the  jjycnometer 
and  tilling  the  pycnometer  a  little  more  than  half  full  of 
warm  water.  The  pycnometer  was  then  attached  to  a  bent 
50  cc.  pipette,  which  contained  some  water.  The  other  end 
of  the  pipette  was  connected  to  the  filter  pump  and  the  air 
exhausted  from  the  powder.  The  vacuum  was  sufficient  to 
cause  the  water  in  the  pjxnometer  to  boil  at  a  temperature 
of  about  30°.  After  no  more  air  bubbles  were  evolved  the 
pycnometer  was  filled  by  raising  the  pipette  and  allowing 
the  air-free  water  to  run  into  the  apparatus.  In  making 
these  determinations  special  pains  were  taken  to  dry  the 
ponder  in  an  air  bath  at  a  temperature  never  less  than 
120  .  Scune  of  the  pycnometers  were  collapse<l  by  the  air 
pressure. 

Conipai'ing  the  specific  gravities  by  the  two  methods 
the  differences  are  shown  to  be  of  the  following  order  of 
majinitude: 


14 


THK    INFLUENCE    OF    FLLXES    AND    NON-FLUXES    UPON     I  HE    CHANGE 


Spec.  gr.  pycnoni I2.69 

Spec.  gr.  suspension    12.55 

Difference    0.14 

Spec.  gr.  pycnom \2.68 

Spec.  gr.  suspension    J2.62 

Difference    1 0. 06 


Spec.  gr.  pycnom.  . 
Spec.  gr.  suspension 
Difference    


Spec.  gr.  pycnoni.  . 
Spec.  gr.  suspension 
Difference    


2.6212.73 

2. 5112.54 
0.11I0.19 

2.65I2.65 
2.61I2.59 
0.0410.06 


2.66  2.6512.67 
5.56  2.61  2.61 
o.io  0.04  0.06 

2. 65  J2.  67  2.66 
2. 6012. 61  2.60 
0.0510.0610.06 


Spec.  gr.  pycnom I2.70  2.65  2.67 

Spec.  gr.  suspension    I2.62I2.62I2.61 

Difference    |o.o8lo.03|o.o6 


2.76  2.65 

2.562.57 
0 .  20  0 .  08 


2.64 
2.61 
0.03 

2.64 
2.62 
0.02 

2.70 
2.59 

O.II 

2.70 
2.66 
0.04 


2.64 

2.57 
0.07 

2.64 
2.61 
0.03 

2.67 
2.60 
0.07 

2.71 
2.60 

O.  II 


2 

.66 

2.67 

2 

58 

2.61 

0 

08 

0.06 

2 

67 

2.67 

2 

63 

2.,S9 

0 

04 

0.08 

2 

64 

2.67 

2 

58 

2.50 

0 

06 

0.08 

2.70 
2.68 
0.02 

2.78 
2.80 
0.07 


2.67 
2.66 

O.OI 

2.73 
2.58 
0.15 


2.68 
2.64 
0.04 

2 . 72  2 .  59 
2.69  2.51 
0.03  0.08 


The  sensibility  of  weighing  in  the  pycnometer  experi- 
ments was  about  0.5  milligram  for  one  balance  and  1  milli- 
gram for  another,  the  average  sample  of  powdered  material 
averaging  8  grams.  The  error  of  weighing  thus  varies 
from  0.005  to  0.01  per  cent.  In  the  suspension  method  the 
weight  of  the  brickettes  varied  from  15  to  20  grams.  The 
sensibility  of  the  balances  was  about  2  centigrams,  which 
corresponds  for  the  15  gram  brickette  to  a  variation  of 
0.13  per  cent. 

From  these  results  it  is  clearly  seen  that  the  specific 
gravity  determinations  by  suspension  are  greatly  af- 
fected by  the  porous  structure  of  the  clay,  that  is,  by  the 
pores  into  which  water  cannot  penetrate.  It  was  recog- 
nized that  in  order  to  obtain  comparable  specific  gravity 
curves  the  true  specific  gravity  would  have  to  be  used..  But 
since  these  determinations  consume  much  more  time,  and 
the  main  aim  of  the  experiments  planned  was  chiefly  a 
practical  one,  it  was  decided  to  use  only  the  apparent 
specific  gravities  and  porosities  in  obtaining  the  rates  of 
vitrification,  since  after  all  it  is  the  rate  and  not  the  abso- 
lute values  that  interested  the  writers  most  at  the  time. 
The  study  of  the  true  specific  gravities  has  been  reserved 


IN    THE    POROSITY    AND    THE    SPECIFIC    GRAVITY    OF    SOME    CI.AYS.  15 

for  inixtiires  whose  toinponents  have  themselves  been  de- 
fined more  closely  by  chemioal  and  physical  methods,  and 
which  are  intended  to  be  simple  mixtnres  rather  than  such 
complex  ones  as  are  afforded  by  the  shales.  By  this  method 
it  was  i)ossible  to  cover  the  j>round  more  rapidly,  and 
about  4000  detei-minations  were  made.  Owin^'  to  this  large 
mass  of  data  it  is  impossible  to  reprmlnce  all  of  the  rate 
curves  thus  obtained,  and  hence  only  the  ty])ical  cases  are 
presented. 

AVe  shall  now  discuss  the  additions  of  tlic  various  re- 
agents to  the  clays  mentioneil  above. 

FELDSrAK. 

Feldspars  are  considered  neutral  body  tiuxes.  By 
this  is  meant  that  their  fluxino-  effect  is  additive,  they 
being  simi)ly  solvents  of  the  clay  substance  and  the  free 
silica.  Feldspar  naturally  lowers  the  melting  point  of  a 
body  most  when  it  is  added  to  the  euteetic  condMnation  of 
kaolin  and  quartz,  which  corres])onds  to  the  ratio  of  1:3. 
This  is  shown  xovy  clearly  in  the  clever  work  of  Dr.  M. 
Simonis*  on  ''Tme  Fusion  Points  of  Mixtures  of  Zettlitz 
Kaolin,  Quartz  and  Feldspar  Fxpresscd  in  Cones." 

By  means  of  a  simple  arithmetical  express^ion,  for 
w  lii(  h  ho  claims  no  theoretical  or  scientific  significance, 
though  he  suggests  its  practical  use,  he  calculates  the  re- 
fractory (piotient  for  bodies  high  in  clay  and  high  in, 
quartz.  In  the  first  case,  that  is,  in  clayey  bodies  in  which 
the  pel'  cent  of  kaolin  is  greater  than  one-third  of  the  per 

cent  of  (juartz,  or  where  K  >  ^^^    Simonis  obtains  his  re- 

fi'actoi-y  (|Uoti('nt  by  the  formula 

K.  F.=K— ''3'  -f+00, 

where  K=%   kaolin 
qwr^fo   quartz 
f-=9^    feldspar. 


*Sprechsaal,  Vol.  40,  Nos.  29  and  30. 


16 


THE    INFLUENCE    OF    FLUXES    AND    NON-FLUXES    UPON    THE    CHANGE 


For  silicious  bodies  in  which 


K  < 


qu 


the  formula  employe  is : 

^-  K 

R.  F.=  A f  -L  60. 

2 

The  number  GO  is  added  to  prevent  negative  values. 
The  values  of  the  refractory  quotient  are  translated  into 
cone  temperatures  by  the  following  table : 


Refractory  quotient  .  . 
Melting  point  in  cones 
Refractory  quotient  . . 
Melting  point  in  cones 


17-5 

22.6 

28.0 

Z3-7 

39.2 

44.6 

50.0 

14.0 

15-0 

16.0 

17.0 

18.0 

19.0 

20.0 

65.0 

72.0 

80.0 

89.0 

102.0 

114. 0 

127.0 

27.0 

28.0 

29.0 

30.0 

31.0 

32.0 

33-0 

57-6 

26.0 

141 .0 

34  P 


From  the  consideration  of  the  Simonis  calculation  it 
is  evident  that  feldspar  plays  the  role  of  a  neutral  flux. 

With  regard  to  the  fusion  process  of  triclinic  feldspars 
we  have  accurate  data  referring  to  artificial  spars,*  which 
had  the  following  composition : 


We  have  here  evidently  mixtures  of  albite  and  anor- 
thite,  and  on  fusing  a  series  of  these  mixtures  it  was  found 
that  they  proved  to  be  a  series  of  solid  solutions  whose 


*Day  and  Allen.     The   Isomorphism  and   Thermal   Properties  of  the 
Feldspars,  Carnegie  Inst.,  1905. 


IN    THE    POROSITY    AND    THE    SPECIFIC    GRAVITY    OF    SOME    CLAYS. 


17 


AJLIAViJO      D(dl03d9 


IS         THE    INFLUENCE    OF    FLUXES    AND    NON-FLUXES    UPON    THE    CHANGES 

melting  points  clianged  in  almost  linear  relation  to  the 
percentage  composition  of  the  two  silicates.  From  this 
result  Day  and  Allen  conclude  tliat  the  triclinic  feldspjfrs 
"form  together  an  isomorphous  series."  This  relation  is 
brought  out  clearly  by  the  curve  of  Fig.  1,  in  which  the 
rate  of  change  in  the  specific  gravity  of  mixtures  between 
the  anorthite  and  albite  is  shown  to  be  a  linear  relation. 
This  tends  to  show  that  we  are  dealing  here  with  isomor- 
phous mixtures  and  at  the  same  time  explains  why  they 
have  no  definite  melting  points.  Albite  was  proven  to  melt 
through  a  range  of  about  150^.  Although  the  melting- 
point  of  the  average  feldspar  as  used  in  the  industries  is 
about  at  cone  8,  yet  its  interaction  with  clay  substance 
begins  at  a  much  lower  temperature.  Berdel  found  that 
the  dissolving  action  of  orthoclase  feldspar  began  as  low 
as  cone  09. 

On  fusing  mixtures  of  the  trilinic  feldspars  it  Avas 
found  that  their  melting  points  were  connected  by  a 
straight  line,  the  same  linear  relation  that  held  for  the 
specific  gravities.  This  shows  likewise  that  the  fusion  of 
the  triclinic  feldspars  is  a  continuous  smoothly  i>roceeding 
process,  and  it  is  even  possible  to  calculate  the  composition 
of  each  point  on  the  curve  from  the  specific  gravity  or  the 
fusion  temperature. 

ADDITION    OF    FP]LDSPAR. 

The  behavior  of  orthoclase  feldspar  is  shown  suffi- 
ciently in  the  porosity  and  specific  gravity  curves  of  Figs. 
2,  3  and  4.  We  observe  that  the  vitrification  due  to  feld- 
spar is  indicated  both  by  the  drop  in  the  specific  gravity 
and  the  decrease  in  porosity.  We  also  find  confirmed  that 
the  solution  effect  of  feldsfjar  begins  at  quite  a  low  tem- 
perature, at  least  as  low  as  cone  06.  It  is  likewise  shown 
quite  distinctly  that  feldspar  is  a  neutral  flux  and  does 
not  undergo  any  chemical  reactions.  The  only  nunimum 
is  that  due  to  the  eutectic  mixture  which,  however,  was  not 
fixed  in  these  series.     The  solution  of  kaolin  by  feldspar 


IN    THE    POROSITY    AND   THE    SPKCIKIC    GRAVITY    OF    SOME    CLAYS. 


i 

1 

K 

rt- 

«S 

' 

ffi 

z     >           ■<»-  <o  o 

O       Qi               Z 

n    S    "=        ^  =  = 

r    •<    in        .0,0  0° 
u.    °    75         ^^0 

— 1 

^ 

\ 

? 

^. 

/ 

/ 

\ 

X 

i 

/ 

J 

> 

o 

y 

/ 

/ 

/ 

/ 

/ 

/ 

in 
z 
< 

y- 

\ 

\ 

n 

N    -^ 

ivi     - 

lA 

l*\ 

— 

tn 

IT 

AllAVMD      0ldl03d9 


0^ 

V. 

'^     "0  ti  ° 

z    >      ^-^-^ 

.      H      t          z 

«J    5    '^      d  =  -~  = 
»     ^     a:       1 .0  5^  0? 
^     <    Z       SSSi 

j- 

_  <0 

^ 

/ 

Y 

^ 

^ 

/ 

/ 

/ 

0 

—                                   -     IVJ     r^ 

a:             0 

■i 

/ 

/ 

n 

0 

/ 

/ 

y 

/ 

\ 

/ 

/ 

^^ 

/ 

/ 

^ 

^ 

,^ 

) 

/ 

/ 

^ 

— ■ 



--' 

/ 

r^ 

^ 

A 

^ 

/ 

/- 

/ 

1 

A 

7 

/ 

Aiisoaod   o/a 


20        THE   INFLUENCE    OF   FLUXES    AND   NON-FLUXES    UPON    THE   CHANGES 
TRANS.  AM.  CER.  50C.         VOL.  X  iLEININGER      AND     MOORE 


i*,— 

FIG     4. 

I3t 

^ 

\. 

si^. 

GEORGIA  KAOLIN 

"^ 

f^ 

c      \ 

PELDSPAR 

45 

40 

^0 

(A 

o 

K  Z5 
o 

"■EO 

'0 

5 

"^ 

R 

h^> 

1       1       1       1       1       1 

X 

^ 

\ 

^  ' 

^ 

">1 

'^ 

s 

L6^ 

h 

fe^s 

h, 

s 

\, 

> 
< 

a 

<. 

v^ 

s 

\ 

c^ 

^ 

J^ 

\ 

o 

N 

, 

o 

\ 

^ 

a. 

100  90 

0  10 


40 

30  4-0  SO  60 

COM  POSITION 


30    KAOLIN 
70     SPAR 


TRANS.  AM   CER    50C        VOL.  X 


8L£ININ0ER   AND    MOORE 


&0 


50 


4-0 


FIGS. 

TENNESSEE  BALL  CLAY  N0.3 

2c 
FELDSPAR 

\ 

V 

0^ 

V 

<;. 

-  C 

^5 

^ 

^ 

V 

^ 

^\ 

. . 

^ 

-^ 

on 

;   7L 



10  20  30  40  50  eO  70  80  90  100   SPAR 

90  80  70  60  50  40  30  20  lO  0    BALL  CLAT 


IN    THE    POROSITY    AND    THE    SPECIFIC    GRAVITY    OF    SOME    CLAYS. 


21 


^ 

/ 

' 

\ 

v9 

• 

u. 

V 

\ 

1 

CANTON    5HALE-5PAR 

POROSITY. 

1 

/ 

/ 

\ 

\ 

\ 

1 

ol 

) 

er^ 

/ 

v/ 

c 

0/ 

Jj 

O 

r 
Q 

( 

U 

\ 

1 

\ 

I 

\ 

\ 

\ 

\ 

V 

) 

V 

) 

o 

ts  o 


<^;;;:; 


«>^ 


vo3: 


in 


<>o 


in 
o 

h 

(L 

o 


w: 


UJ 


AUSO^Od  % 


22        THE    INFLUENCE    OF    FLUXES    AND   NON-FLUXES    UPON    THE   CHANGES 

TRANS.  AM.  CER.  SOC        VOL.X  BLEl  NINGER  /\N0  MOORE 


50 

FIG. 7. 

CANTON  SHALE-SPAR 
POROSITY 

NO.I      100%  SHALE 

Z      99%       "         l%SPAR 

3  9G%       »        A°'o     y> 

4  94%      "        G%     y 
S      9  2  %      »         ft  %>     " 

4-5 

40 

35 

5^ 

^ 

'^^w 

6      90%      «         10%     n 

30 

^ 

^ 

^ 

X 

^ 

^ 

•     25 

N; 

\ 

^ 

\ 

^ 

N 

i 

«0 

^ 

\ 

^^^ 

\ 

O 

a: 
Q- 

r 

s> 

\, 

\ 

\ 

sN 

0^ 

10 

v\ 

\, 

N 

\ 

> 

V 

<^ 

^^ 

^ 

1,2. 
4- 

5 

\ 

s 

5 

X. 

--- 

& 

09 


06  03 

CONES 


01 


IN    THE    POROSITY    AND   THE    SPICCIKIC    GRAVITY    OF    SOME   CLAYS. 


23 


takes  place  at  a  fairly  rapid  rate,  which  shows  simply  that 
there  seems  to  be  no  physical  obstacle  to  this  mutual 
solution. 

The  curves  also  bring  out  the  ditterence  in  the  behavior 
of  Georgia  kaolin  and  Florida  kaolin. 

In  Fig.  5  we  have  the  porosity  curve  of  mixtures  of 
Tennessee  ball  clay  No.  3  with  feldspar,  and  it  is  evident 
that  feldspar  in  this  case  becomes  far  more  potent  in  its 
action  than  in  the  cases  of  the  two  kaolins. 

The  effect  of  various  percentages  of  feldspar  upon 
Canton  shale  is  shown  in  Fig.  6,  and  we  observe  that 
though  the  first  additions  cause  a  small  decrease  in  poros- 
ity, the  result  shows  practically  no  gain  in  fusibility  or 
^itrifi cation.  The  same  fact  is  brought  in  Fig.  7,  in  which 
some  of  the  shale-spar  curves  are  arranged. 

In  this  connection  it  was  also  interesting  to  observe 
the  action  of  Cornish  stone  on  kaolin  as  shown  bv  Fig.  8. 


TKANS    AM   CER    &0C.       VOL.  X. 


BLEININGER  ANQ  MOORE 


AO 


FIG.  8 
FLORIDA  KAJliN 

8£ 

^=; 

-^ 

"^ 

^ 

^^ 

^ 

^ 

N 

\ 

^d 

[^ 

\ 

X 

\ 

N? 

-^ 

\ 

sr 

N 

X 

Sf 

^ 

^ 

Co 

k". 

^ 

\^ 

\ 

r 

^^ 

> 

K 

s 

^ 

\ 

^ 

^ 

X 

^ 

\ 

CORNWAU  STONE  10 

20            30            m 

50 

60 

70 

80 

KAOLIN  90 

SO              70              60 
C  0  M  PC  5ITI0N 

50 

.40 

30 

20 

24         THE    INFLUENCE    OF    FLUXES    AND    NON-FLUXES    UPON    THE    CHANCES 

Here  we  uote  distinctly  the  slow,  ueutral  fluxinj^  effecL 
of  this  material  whose  action  is  more  gradual  than  that  of 
tlie  feldspar  and  which  offers  the  safest  flux,  as  far  as 
range  and  rate  of  vitrification  are  concerned. 

THE   ADDITION   OF   LIME. 

Kaolin  and  Ball  Clay.  In  the  addition  of  calcium 
carbonate  to  clays  we  are  dealing  with  a  flux  which  is 
unlike  feldspar  or  Cornish  stone.  Its  action  is  not  gradual, 
but  variable;  that  is,  though  its  presence  may  not  be 
observed  by  means  of  the  porosity  curve,  at  the  proper 
reaction  temperature  it  suddenly  combines  and  causes  as 
large  an  amount  of  fusible  magma  to  be  formed  as  is  con- 
sistent with  the  composition  of  the  body.  At  the  same  time 
there  is  to  be  considered  the  fact  that  lime-alumina-silica 
compounds  form  a  number  of  maximum  and  minimum  fus- 
ing compounds.     This  has  been  clearly  shown  in  the  work 


TRANS.  AM.  CER,  SOC.   VOL.  X 


BLEININGER   AND    MOORE  . 


37, 

35 

33 

31 

23 

ZV 

20 

"J  18 
Z 

olfe 
U 
14 


I/) 


FI0.3. 

1 

_ 

p 

-- 

^ 

r 

\  X         •        « 

K                                > 

^ 

u 

\        / 

X 

N  ____^ 

^ 

\ i 

/ 

\ 

s    / 

i 

i 

S. 

\    ^ 

\a 

f 

V 

1.5    Z.0    Z.5  3,0  i5   M    4:5    SO    5.5    fiJ)    6.5    ZO    75    8J)   8.5   9.0    9.5    10.5    10.5   II.O    11.5    \ZJI 
MOLECULES    CaO      TO    1   MOLECULE  Alg^O^  •  ZSiOg^ 


IN    THK    POROSITV    AND    THE    SPKCIFIC    GRAVITY    OF    SOME    CLAYS. 


2o 


of  Rieke,*  who  investigated  the  melting  points  of  mixtures 
of  this  kind  in  a  most  thorough  and  exliaustive  piece  of 
work,  using  an  electric  carbon  lesistance  furnace  for  the 
determination  of  the  melting  points.  We  shall  consider 
only  his  results,  referring  to  the  AUOg :  2  Si02  mixtures 
and  those  higher  in  silica.  The  first  curve  brings  out  the 
fact  already  noted  by  (Jramerf  that  for  high  temperatures, 
additions  of  CaO  to  kaolin,  up  to  10%,  decrease  the  melt- 
ing point  in  equal  intervals.  The  lime-kaolin  fusion  curve 
of  Kieke  is  reproduced  in  Fig.  0,  the  abscissa  indicating 
the  molecules  of  CaO  to  1  molecule  of  AloO^  :  2  SiOo,  the 
ordinates  the  melting  points  in  cones.  With  a  content  of 
10%  CaO  we  have  a  minimum  corresponding  to  the  for- 
mula CaO,  .2  AI2O3,  .4  SiO..  On  increasing  the  lime  we 
find  a  maximum  at  the  com])osition  CaO:Al.jO;::2  SiOo. 
With  more  lime  the  fusion  curve  descends  again  to  a  mini- 


TRANS 

AM     CER.  SOC     VOL  X 

BLEININGER 

ANO  MOORE 

FIG.  10 

' 

\ 

^ 

30 

1 

^ 

Y^ 

^ 

y\ 

r' 

-^ 

^ 

f 

IS 

/ 

(OIV 
UJ 

2  15 
0 
0  IJ 

1 

1                              / 

W^ 

\ 

\                              / 

9 

\ 

K 

\                         1 

/ 

Vn 

i-n 

05     li)    1.5     I     Ih    iJ)    i.5    +0    4.5    SH    5.5    M     6.5    70    Z5    8.0    B.5  9.0    3.5    IttO   105    IID   ir.5   IJ.O 
MOLECULES      OF      CcxO     TO    1  MOLECULE    AljOiOSnOi 


*SprccIisaal,  Vol.  40,  Xos.  44,  45,  46. 
tTonindustrie-Zeitung,  1887,  p.  197,  ami  1888,  p.  •]2,. 


26 


THE   INFLUENCE    OF    FLUXES    AND    NON-FLUXES    UFON    THE   CHANGES 


mum  2  CaO :  AI2O3  2  SiOo,  which  is  tlie  most  fusible  com- 
bination between  kaolin  and  lime  that  exists  correspond- 
ing to  a  percentage  composition  of  36.1%  SiOg,  30.5% 
AI2O3  and  33.4%  CaO.  On  increasing  the  lime  still  more 
Rieke  obtained  a  second  maximum  at  4  CaO  :  AUOo :  2  SiO. 

This  is  followed  by  a  third  minimum  6  CaO :  AI2O3 : 
2  SiOj.  After  this  it  appears  that  no  further  decrease  in 
melting  point  occurs.  Since  the  maximum  and  minimum 
points  very  likely  correspond  to  chemical  coml)inations,  it 
seems,  according  to  Rieke,  that  there  exist  at  least  four 
distinct  compounds  of  lime  and  kaolin. f 

In  the  mixtures  of  CaO  with  AloOo :  3  SiOo  shown  in 
Fig.  10,  there  are  observed  four  maxima  and  four  minima 
which  appear  to  show  the  existence  of  the  following  com- 
pounds and  mixtures: 


TRANS. 

AM.   CEK.  S.OC 

VOL.X 

BLEifJINGER 

AND 

M03RE 

FI6.ll 

34 

32 

30 

28 

26 

19 

17 

iul5 
z 

°I3 
0 
II 

I 

\ 

\ 

1                ■                                                    ^ 

r ! 

\                                                                                                              /^ 

! 

\  \                                                                                                     ^\ 

k 

/  1 

i 

\ 

y 

1 

1 

9 
7 

i 

\ 

y 

1 

^-                               ^ 

f 

\, 

^-x^ 

< 

5 

J 

-J 

\^ 

r^^v— -r"^ 

'\ 

0.5     1.0      1.5     U     1.5     3.0     3.5     4.0     +.5      5.0     55     fc.O     6.5     7.0     7.5      8.0     g.5    90     S.5     lO.O 
MOLECULES    CaO     TO    1  MOLECULE     AlzO^-^SiO^ 


tRieke's  view  that  the  minimum  as  well  as  the  maximum  points  cor- 
respond to  chemical  compounds  is  open  to  criticism.  The  minimum  points 
;irc  probably  eutectic  mixtures. 


IN    THE    POROSITY    AND    THE    SPKCIFIC    GRAVITY    OF    SOME    CLAYS. 


27 


CaO 

7  CaO 

3  CaO 

5  CaO 

13  CaO 


2  Al,03 

4  AI0O3 

Al.O, 

AloO., 

2  A1.,0.. 


6  SiOo 

12  SiOo 

3  SiOs 

3  SiOo 


CaO  Al.,03  3  SiO, 

2  CaO  AI0O3  3  SiO, 

4  CaO  ALO3  3  SiO, 

6  CaO  A1.,0..  3  SiO. 


6  SiO.. 


Finally  iu  mixtures  of  lime  with  AI2O3  and  Si02  Rieke 
found  one  rather  indistinct  maximum,  5  CaO :  2  AJ^OaiS 
SiOs  and  two  minima,  Fig.  11.  The  curve  as  a  whole  is 
more  regular  than  the  preceding  ones. 

It  is  evident  from  these  data  that  we  cannot  expect 
from  lime-clay  mixture  the  regularity  of  fusion  induced  by 
feldspathic  fluxes,  and  it  remains  to  be  seen  how  the  vitri- 
fication of  different  clays  is  affected  by  this  flux. 

Lime — Florida  Kaolin  Mixtures.  Inspection  of  curve 
of  Fig.  12  shows  clearly  that  with  increasing  lime  content 
at  Cone  06  but  little  change  occurs  within  the  compositions 
examined,  the  mixture  containing  10%   whiting  showing 


TRANS.  AM    CER    50C.    VOL.X. 


BLEININGER    AND  MOORE 


50 


40 


v30 

h; 

o 

o 
Q. 


FLO 

RID/ 

FIC 

POP 

OLIN-W 
lOSITY 

1 

HIT 

INQ 

. 

■ — 

-^ ' 

' 

~ 

Co 

ne 

06 

~~~" 

^ . 

-^ 

CO 

1-1  e 

^ 

^ 

-V" 

__^ 

— 

? 

c 

-o> 

le"^ 

■^ 

\ 

S, 

/ 

V 

\ 

/ 

WHITING      I 
BALL  CLAY  'i^ 


3 
97 


4  5 

96  95 

COM  POSITION 


10 
90 


28         THI£    INFLUENCE    OF    FLUXES    AND    NON-FLUXES    UPON    THE    CHANGES 

ouly  4%  less  porosity  than  the  composition  99. 57^  kaolin, 
0.5 7  whiting.  We  also  observe  that  the  first  2%  of  whit- 
ing in  tlie  Cone  9  curve  are  more  eifective  in  decreasing 
porositA'  tlian  3-6%,  a  second  decrease  in  porosity  taking 
place  only  bej'ond  C/o  whiting.  Of  course  this  is  in  agree- 
ment with  the  general  theory  of  dilute  solutions  as  sug- 
gested by  Ludwig. 

On  studying  mixtures  of  ball  clay  and  larger  amounts 
of  lime  we  observe  in  the  specific  gravity  curve,  Fig.  13,  a 
distinct  minimum  in  the  Cone  09,  03,  and  2  burns  at  about 
30%  whiting  and  70%  ball  clay,  which  corresponds  roughly 
to  the  minimum  CaO :  AI2O3 :  2  SiOg  observed  by  Rieke. 
This  seems  to  be  the  eutectic  composition  under  these  tem- 
perature conditions.  The  corresponding  porosity  curve, 
Fig.  14,  shows  two  maxima  and  minima,  the  first  maximum 
being  at  30 7o  whiting  and  70%  ball  clay,  the  second  at 
50%  clay,  50%  whiting.  The  minimum  is  at  40%  whiting, 
60%   ball  clay,  a  second  minimum  is  indicated,  but  not 


iiO 

TRAN6 

AM 

CER.   SOC. 

V'OLK 

BLEININGER     AND    MOORE 

FIG    13. 
:SSEE    BALL   CLAY  N23 

/ 

^ 

TENNE 

Qot  CO3 

I 

Y 

J, 

^ 

/ 

/ 

/ 

/ 

/ 

J 

/ 

1/ 

/ 

i 

,i...O 

0 

4 

:2.30 

0/ 

/ 

/ 

/ 

^ 

CaCOj  10 

20 

30              40 

50 

60 

70 

80 

id 

100 

ML  CLAY  90 

80 

70               60 
COM  POSITION 

SO 

40 

30 

20 

10 

0 

IN    THE    POROSITY    AND    THE    SPECIFIC    GRAVITY    OF    SOME    CLAYS. 


29 


reached.  Of  t-ourse  it  would  be  idle  to  claiiu  that  these 
maximum  points  actuallv  do  represent  certain  compounds, 
as  we  must  remember  that  the  apparent  specific  gravities 
are  the  resultants  of  a  number  of  factors,  of  which  not  the 
least  important  is  the  temperature  to  which  each  brickette 
was  raised  in  the  kiln.  It  would  be  claiming  too  much  to 
say  that  each  brickette  actually  reached  or  did  not  exceed 
the  temperature  of  the  burn  as  indicated  by  the  cone  in 
each  sagger.  There  must  have  been  temperature  differ- 
ences. ^Vnother  verj'  important  factor  in  the  curves  repre- 
senting a  series  of  compounds,  is  the  constantly  changing 
initial  specific  gravity  of  each  mixture  as  we  start  from  one 
side  of  the  curve  sheet  to  the  other.  For  instance,  the  last 
series,  on  going  from  left  to  right  increases  in  lime.  Every 
increase  in  CaO  thus  means  a  change  in  specific  gravity, 
and  this  should  be  borne  in  mind  in  examining  subsequent 
curves.  If,  now,  in  spite  of  these  factors,  certain  maxim  i 
and  minima  occur,  coinciding,  at  least  in  most  cases,  with 


70 

TRANb. 

AM 

CER 

soc 

VOL  X. 

8LEININGER    AND  MOORE 

/ 

-V 

FIG  14. 
TENNESSEE    BALL  CLAYf 
Ca  CO  3 

4s 

s. 

S3 

/ 

11 

\ 

^ 

2. 

'iii 

' 

\V 

\ 

01 

40 

f 

til 
1^1 

1 

\^ 

03 

/ 

"V 

< 

!h 

\ 

> 

/ 

/ 

1 

\ 

06 

J 

y 

-N, 

M 

06 

o 

DC 

a. 

i 
1,03 

^ 

^ 

N 

vl\ 

^ 

\ 

(jj 

n5> 
10 

10  20  30  -VO  50  60        Ca  CO, 

90  90  70  60  50  40       BALL   tlAY 

C  0  M  P  0  SITIO  N 


30         THE    INFLUENCE    OF    FLIWES    AND    NON-FLUXES    UPON    THE    CHANGES 

similar  points  in  the  porosity  curves,  we  are  led  to  the 
conclusion  that  certain  phenomena  are  taking  place.  The 
technical  side  of  the  vitrification  progress  is  represented, 
of  course,  by  the  porosity  curves.  In  Fig.  15  the  action  of  6 
and  9.5%  respectively  of  whiting  is  shown  for  the  lower 
temperatures,  and  we  observe  tliat  the  decrease  in  porosity 
begins  about  between  cones  Ofi  and  01. 


TRANS.  AM    CER    50C.      70L  X 


BLEININGER    AND   MOORE 


(LIO 


FIG  15. 

FLORIDA  KAOLIN-WHITING 
POROSITYANO  SPECIFIC  GRAVITY. 


1=    90.5%KA0LIN-9.57oWHITING 
Z  *    fl+.0%      >>      -  6.0%) 


3.1 


2.7 


< 

a: 
o 

2.3 


1.9 
1.7 


03  06  03  Oi  2  + 

CONES 

Shales.  In  the  porosity  curves  of  mixtures  of  Hanton 
shale,  Fig.  16,  and  whiting  we  observe  that  the  lime  begins 
to  act  as  a  refractory  substance  in  percentages  that  vary 
with  the  temperature.  In  the  Cone  06  curve  almost  the 
first  addition  of  lime  seems  to  increase  the  porosity,  while 


IN    THE    POROSITY    AND    THE    SPECIFIC    GRAVITY    OF    SOME    CLAY'S. 


31 


Hie  iiicreasi'  in  the  ('one  01  and  2  eiirves  be<>ins  vitli  1.5 
and  4.5%  respectively.  The  significance  of  the  minimum 
with  the  0%  addition,  if  it  really  is  a  minininm,  remains 
lo  be  explained.  From  general  considerations  it  api)ears 
that  the  porosity  at  about  that  point  ought  to  decrease. 

The  rate  at  which  this  shale  decreases  in  specific 
gravity  and  porosity  is  shown  in  Fig.  IT,  and  brings  out 
the  fact  that  the  porosity  tends  to  increase  up  to  Cone  06, 
and  from  this  point  on  shows  a  rate  of  decrease  slower  than 
that  of  the  pure  shale.  But  after  passing  Cone  03  its 
vitrification  becomes  decidedly  more  rapid  than  that  of 
unmixed  shale,  as  we  know  to  be  the  effect  of  lime. 

In  Fig.  18,  representing  mixtures  of  Crawfordsville 
shale  and  whiting,  we  observe  a  very  decided  increase  in 
porosity  between  Cones  Ofi  and  03,  followed  by  an  ex- 
tremely sudden  drop  between  03  and  01.  The  increase  in 
porosity  after  vitrification  has  been  reached  is  also  quite 
marked  in  .some  of  the  lower  lime  mixtures. 


TRANi.   AM    CER     SOC       VOL  X 


BLEININGER     AND   MOORE, 


50 
45 
40 
35 

:^Z5 


a. 


FIG  16. 

CANTON   SHALE  ANOWHITING 

1 

f 

g-*> 

e  0 

b 

^ 

N 

^ 

^ 

— ■ 

==* 



— 

-^ 

C 

gtx< 

p^ 



^ 

^ 

^ 

V 

y 

^ 

r  < 

.^^ 

J^ 

\ 

S, 

/ 

-^ 

^ 

y 

^ 

^^ 

/ 

^ 

^ 

X 

— ' 

s 

"— 

i 

— ^ 

.^ 

SHAlflOO 

WHITING 


97 

96             95 

94 

93 

9Z 

SI 

90 

3 

4               5 
PER     CENT 

fo 

7 

8 

9 

10 

32        THE    INFLUENCE   OF    FLL'XES    AND    NON-FLUXES    UPON    THE    CHANGES 


Of 

00 
U. 

?           «^    ^ 

< 

>0 

s  -  -  « 

Qi 

o 
u. 

i 

o5   o    en    "Ji 

»     II      »      # 

—    <vj     fO     + 

cj    o    o    o 

-zi-z.-z.-z. 

ILI 

r 

z 

M. 

,tOJ 

^^ 

-^ 

7^ 

'\ 

_^ 

-^ 

-^ 

/ 

A 

,-^ 

^ 

^ 

^ 

^^^ 

y 

>< 

,< 

^ 

^ 

- — 

ITj 

^ 

— 

Y 

7^ 

o 

> 

^ 

/ 

^ 

^ 

o 

/ 

#/ 

I* 

^ 

^ 

OL 

V 

o 

z 

/ 

/ 

S 

1 

/ 

f 

z 

\ 

y 

/ 

/ 

f 

Df 

t 

> 

y 

o  U 

z 


Aiisoa  od  9& 


1 

1 

o 

z 

b  =  = 

1  ^  S  ^^- 

t3  :^  -.■  c 

LU 

•t 
X 

z     -      ~ 

y~ 
z 

01    tn    CD    « 

—    ivj    /T)    <; 
O    O    O    c 

z  z  z  : 

o 

z 

^ 

/ 

z 

*x 

f 

3 

> 

-^ 

-J- 

^ 

y 

^ 

^ 

^ 

/ 

3        _ 
3 

\        - 

6 

/ 

^ 

/ 

/ 

/ 

X 

V 

/ 

/ 

/ 

y 

y 

5 

/ 

/ 

^ 

y 

y^ 

o 
in 

y 

/ 

y 

^ 

a: 
o 

y 

< 

J 

^/ 

/ 

i 

/ 

/ 

< 

v. 

K 

( 

•o 


KXISOyOd  % 


IN    THE    rOROSlTY    AND    THE    SPECIFIC    GRAVITY    OF    SOME    CLAYS. 


33 


The  Galesbiirg  shale,  Fig.  19,  was  less  affected  by  the 
lime  added  than  the  two  other  shales  at  Oone  2,  but  at 
Cone  4  the  mixtures  had  gone  considerably  beyond  viscous 
vitrification  and  had  stuck  to  the  saggers. 


TRANS.  AM. 

:er 

soc 

VOL.X 

BLEININ&E.R  AN0MOOf?£ 

FIQ.19. 
GALESBURG  SHALE-WHITING 
POROSITY 

40 

NO  Z          95.5%       "              4-. 5  *  WHITING 

N0  + 

3 

s 

2    "a 

>      '               fo.S  ~/c 

„ 

J- 

-^ 

^ 

,vs 

^^ 

-^ 

\ 

i 

i 
V 

30 

\ 

1 

\ 

s. 

\ 

\ 

\ 

^ 

25 

\, 

\ 

I 

\ 

\, 

\ 

w 

20 

\ 

< 

\\ 

, 

\ 

V 

V 

\ 

4 

. 

\ 

V 

-~ 

\ 

2 

vl5 

1- 

\ 

\ 

3 

O 

KIO 
o 

a. 

V 

1 

5 

09 


06 

CONES 


03 


With  regard  to  the  effect  of  lime  introduced  as  the 
carbonate  we  may  say,  therefore,  that  it  is  not  a  neutral, 
gradual  flux,  but  evidently  there  are  produced  several  com- 
binations of  lime  with  the  other  constituents  of  the  clay 
which  are  available,  wliich  give  risee  to  curves  showing 
maximum  and  minimum  points.  This  is  the  case  especially 
with  larger  amounts  of  lime.    This  effect  naturally  is  more 


34        THE   INFLUENCE   OF    FLUXES    AND    NON-FLUXES    UPON    THE    CHANGES 

prominent  at  higher  temperatures.  The  fluxing  effect  of 
small  amounts  of  lime  on  high  alumina  cIsljb  is  not  marked 
at  lower  temperatures,  as  evidently  such  temperature  as 
Cone  2  are  not  jet  within  the  temperature  zone  of  its 
activity. 


50 
3 

TRANS. 

AM 

CER 

soc 

VOL.X 

BLEININGEP 

AND  MOORE 

'I 

45 

_ 



*^, 



^ 

s^ 

►    40 

s 

V 

\su\ 

35 

\ 

^ 

V 

\ 

c^ 

\^ 

30 

^ 

^ 

s,^ 

^ 

" 

I 

25 

>- 

v^ 

3 

\ 

o 
0. 

\ 

2 

\ 

4- 

15 

FIG. 20. 

FLORIDA  KAOLIN -Fei03 
POROSITY  CURVES. 

10 

- 

N0.1    =  92°/bKA0LIN     6%   FezO^ 

N0.2  »  100  %        » 

NO. 3  .   94^0        '>           6%         " 

5 

^                       ■ 

JU.+ 

=  y 

feVo 

)) 

+  7o 

» 

03  06 

CONES 


03 


In  ferruginous  shales  containing  lime  the  maximum 
fluxing  effect  is  shown  by  not  more  than  5%  of  the  car- 
bonate. Any  increase  above  this  amount  seems  to  produce 
refractoriness  at  temperatures  up  to  Cone  2  inclusive. 
The  amount  of  lime  drawn  into  reaction  increases  with  the 
temperature;  while  at  Cone  06  it  does  not  seem  to  have 


J 


IN    THE    POROSITY    AND    THE    SPECIFIC    GRAVITY    OF    SOME    CLAYS. 


35 


taken  part  in  the  condensation  of  the  body,  at  Cone  01  its 
etfect  is  noticeable.  In  re<>ard  to  its  «>enei'al  behavMor  in  a 
pavinji;  brick  shale  we  must  say,  of  course,  that  it  is  an 
undesirable  constituent,  not  on\j  because  of  its  sudden 
rtuxino-  effect,  but  also  because  of  its  tendency  to  produce 
vesicular  structure. 


TRA 

NS. 

AM 

CER 

soc 

VOL 

X 

BLEININGeF 

AND  MOORE 

Fie.2i. 

CANTON  SHALE 

Fea03 

NO  1     >     100  "o  SHALE 

NO  2.    ^      90'c 

lO-'bFe2  03 

40 

N0  3    =      94%        " 

6%       J'              1 

NO 4  -    ge.s^o    " 

N0  5    »      99    %     '- 

3.5  "j     "            j 

2 

i-'o       "    , 

35 

4 

A 

1          1 

J 

\ 

K 

25 

\ 

^ 

20 

\ 

V 

\ 

^ 

>- 

V 

tl5 

\ 

\ 

tfl 

\ 

k 

\ 

^ 

vv 

u: 

S, 

^\ 

N 

2 10 

\. 

^c 

k 

\ 

\, 

^: 

\f^ 

N 

>V-, 

4 

0^ 

\ 

\ 

\ 

V 

■^ 

1 

5 

s 

•s^ 

-■^ 

-^ 

N, 

s^ 

'*■ 

N. 

^ 

2 

\, 

■ 

■^ 

5 

09  06 

CO  NE5 


03 


ADDITION    OF    FERUIC    OXIDE. 

In  the  series  in  which  we  have  mixtures  of  clay  with 
increasinp^  amounts  of  ferric  oxide,  it  is  evident  that  each 
increase  in  iron  results  in  an  increase  of  specific  uravity, 
and  hence  specific  gravity  curves  are  of  little  value  in  this 
connection. 


36        THE   INFLUENCE   OF   FLUXES    AND -NON-FLUXES    UPON    THE    CHANGES 

Florida  Kaolin.  From  Fig.  20  we  observe  at  ouce  that 
iron  oxide  is  by  no  means  an  active  flux  when  combined 
with  clay  substance,  for  while  a  small  amount  seems  to 
exert  some  fluxing  action,  its  general  tendency  seems  to  be 
a  rather  indifferent  behavior.  The  areas  inclosd  by  the 
100%  kaolin  and  the  kaolin-iron  mixture  curves  give  some 
measure  of  the  fluxing  effect  of  the  ferric  oxide.  It  is  noted 
that  in  part  of  the  curves  the  ferric  oxide  behaves  as  a 
refractory  agent. 

In  the  shale-ferric  oxide  series  practically  the  same 
effects  are  observed.  In  the  Cone  2  curve  up  to  an  addition 
of  2.57c  of  ferric  oxide  a  small  decrease  in  porosity  is  ob- 
served, after  which  the  iron  seems  to  behave  as  a  neutral 
agent.  More  iron  tends  to  make  the  clay  more  refractory 
up  to  a  certain  point.  There  is  no  doubt  but  that,  if  the 
iron  were  increased  still  more,  one  or  minimum  and  maxi- 
mum paints  would  be  reached,  for  in  the  90%  Canton 
shale — 10%  FeoOg  curve  the  fluxing  effect  becomes  quite 
marked.  Fig.  21  shows  the  effect  of  the  ferric  oxide  upon 
this  shale  by  the  areas  enclosed  between  the  two  porosity 
curves.   The  other  shales  behave  in  much  the  same  manner. 

We  may  conclude  from  these  results  that  ferric  oxide 
is  not  an  effective  flux  when  combined  with  clay  substance, 
nor  has  it  a  very  marked  influence  upon  ferruginous  shales. 
In  the  first  case,  perhaps  due  to  the  lack  of  free  silica,  in 
the  second  due  to  the  large  amount  of  iron  already  present. 
At  the  same  time  the  ferric  oxide  behaves  as  a  slow  acting 
and  safe  flux.  An  excess  seems  to  promote  the  formation 
of  a  vesicular  structure,  and  it  might  be  that  in  the  shale- 
iron  oxide  curves  with  varying  percentages  the  increase  in 
porosity  is  due  to  this  cause. 

The  hypothetical  case  of  adding  iron  oxide  to  clays  in 
order  to  make  them  more  suitable  for  the  manufacture  of 
paving  brick  seems,  therefore,  not  to  be  well  taken,  though 
some  patent  specifications  prescribe  such  a  mixture. 


IN    THE    PORCSITY    AND    THE    SPECIFIC    GRAVITY    OF    SOME    CLAYS.  lil 

TRANS.    AM  CER     SOC      VOU.X.  BLElNINQER     AND  MOORE 


50 


4() 


t-iO 


Ol 


K/ 

lOLI 

FIG. 22. 
N   Sc    FLINT 

1 



CO 

ie 

9 

kV 

'  ^ 

c.c'';^^^^^''^ 

.^.— - 

1 

^ 

^^ 

Vi^ 

^ 

^ 

FLINT   10  20  30  40  50  60  79  80 

KAOLIN  90  80  70  60  50  40  30  20 

C    0    MPOSITION 


TRAN6.   AM    CER    50C      VOLX. 


BLEININGER     AND     MOORE 


FLINT   Z. 

4               6               8 

10 

12 

14 

16 

18 

20 

CAMTON  SHALE  98 

96            94            92 
CO  MPOSITION 

90 

88 

86 

8^ 

82. 

80 

38         THE    INFLUENCE    OF    FLUXES    AND    NON-FLUXES    UION    THE    CHANGES 

ADDITION   OF   FLINT. 

Florida  Kaolin.  As  is  to  be  expected,  the  kaolin-flint 
series  produce  curves  showing  increase  in  porosity  with 
increase  in  flint,  Fig.  22. 

Shales.  Mixtures  of  Canton  shale  and  flint,  Fig.  23, 
showed  a  remarkable  drop  in  their  porosity  curve  at  the 


TRANS. 

AM 

ZBR. 

soc 

VOL.X 

BLEININGER    AND  MOORE 

FIG. 24- 

^ 

CANTON  SHALE-FLINT 

45 
t 

^ 

N 

s 

POROSI 

1 

TY. 

^ 

40 

^ 

35 
4 
3 
1 

30 

N 

S, 

s 

S 

Z 

N 

NO  r     100%  SHALE 

NO  2      90%      »       IO%FUNT 

NO  3      89%      "      11%     " 

s 

\ 

k 

s 

25 

\ 

N 

\ 

N04 

V 

b"/o 

„      ZA 

% 

' 

\ 

\, 

\ 

N 

\ 

^ 

\ 

N, 

20 

\ 

> 

\\ 

>- 
t-    , 

\ 

\ 

V 

^ 

S 

V 

a: 

o 

N 

^ 

N, 

s 

4- 

D-  (0 

1 

X 

\ 

^ 

/ 

/ ' 

1 

\ 

b 

V 

y 

i 

05 


composition,  90%  shale,  11%  flint.  Up  to  this  proportion 
the  porosity  of  the  shale  mixtures  for  each  temperature 
kept  about  constant.  This  drop  is  simultaneous  in  all  of 
the  temperature  curves,  and  clearly  indicates  that  a  far 
reaching  change  took  place  at  this  point.  The  practical 
conclusion,  hence,  would  be  that  10%  of  fine  flint  acts  as 


IN    THE    POROSITY    AND    THE    SPECIFIC    GRAVITY    OF    SOME    CLAYS. 


39 


ii  flux  ill  this  shale,  formiug  probably  an  easil}^  fusible 
silicate  with  the  iron  oxide  and  other  fluxes.  In  mixtures 
of  Galesburo-  shale  and  flint  two  drops  were  observed  in 
the  porosity  curve,  though  neither  one  of  tliem  was  well 
defined,  one  at  89^r,  the  other  at  IS^^  flint.     In  the  Craw- 


TRANS   AM   CER     SOC 

/OL  X 

BUININ&ER  A-iO  MCJRE 

40 

FIG.iS. 

NO  1  '   96%GALESBURG5HALE   4fcFLINT 

NO  2  '  100  %                  >•                  0  %     » 
NO  3-    93%                 "                  7%      » 
NO  4  •    9Z.'"^o                 »                  6%      » 
NO  5  =    90%                 •>                 10%     » 

35 

NO  fc  •    Zb%                 »                  l+%     » 

1 

^V 

!      1 

30 

3 

^ 

fe 

1 

^V 

' 

zs 

S^          ^ 

1 

\  >^ 

1 

V 

^ 

^i>M 

1 

\ 

^vH^.^  \ 

o 

Ik. 

\ 

\ 

\\^ 

^ 

> 

\    \ 

\^ 

iO 

N 

r^^ 

v\' 

V 

5 

\ 

i^^^ 

z 

\ 

K. 

1   \ 

<b 
3 

s 

^-- 

■ 

5 
4- 

09  06  03  01  2  4 

CONES 

fordsville  shale  mixtures  the  Cone  2  curve  likewise  showed 
two  minimum  points,  one  at  10%,  the  other  at  19%  flint. 
These  points  also  were  not  as  well  defined  as  the  point 
observed  in  the  Canton  shale,  though  more  distinct  than 
in  the  Galesburo;  shale. 

Referring  to  the  absolute  fluxing  effect,  there  is  no 
gain  as  regards  increase  in  fusibility  by  the  addition  of 


40         THE    INFLUENCE    OF    FLUXES    AND    NON-FLUXES    UPON    THE    CHANGES 

TRANS.  AM  CER.  50C.      VOL  \  BLEININCaER    AND  MOORE 


40 


35 


30 


Z5 


20 


tl5 
(/) 
o 
a: 


CR/i 

^WF( 

)RDS 

Fia.26. 

VILLE   SHALE -FLINT 
OKOSITY 

! 

£^ 

v^ 

1^= 

^ 

^^J\ 

NO.I  «  100% SHALE 

"^ 

y 

N0.£  «    22)%      »       a% FLINT 
N0.3  =    95%     »       5%      » 

\ 

\ 

N0.4*    91  "/o     )>       3%      » 

i 

In 

^ 

N0,5«    90°/o     »       \0fo      » 

\ 

^ 

^. 

M 

^ 

k 

^ 

N. 

S 

N 

\ 

^ 

V 

V 

X 

^^ 

--- 

^ 

5 

09  06 

CONES 


03 


01 


IN    THE    POROSITY    AND    THE    SPF.CIFIC    GRAVITY    OF    SOME    CLAYS. 


41 


tlint  to  Cauton  shale.  Auy  addition  of  tiint  at  oiue  makes 
the  (lav  more  refractory  until  11^/^  have  been  added,  when 
the  drop  occurs.  At  the  last  point  the  mixture  seems  to  be 
but  a  trilie  more  refractory  than  the  unmixed  shale,  Fig. 
24.  The  rate  of  vitrification  does  not  seem  to  be  affected; 
if  at  all,  it  is  in  the  direction  of  safer  buruinii,. 

The  Galesburg-  shale  mixtures  with  flint  show  a  de- 
cidedly lower  vitrification  range  than  the  pure  shales,  and 
it  seems,  hence,  that  in  this  case  flint  acts  as  a  pronounced 
flux.  Fig.  25. 

In  the  Crawfordsville  shale  the  flint  acts  distinctly  as 
a  flux  up  to  5%,  and  at  the  same  time  it  disturbs  the  rate 
of  vitrification  unfavorably.  Fig.  2G.  Above  5%  the  refrac- 
tory character  of  flint  appears,  which  is  maintained  until 
10%  have  been  added.  In  this  case  also  the  rate  of  vitrifi- 
cation is  changed  in  an  undesirable  manner. 


TRANS   AM  CER   SOC     VOlX 


BLElNlNGER     AND     MOORE 


100     96     38     97     96     9S     94     93     91     91      90     89 
01        2345       6736      10      II 
C  OMPOSITION 


87     86     SHALE 

13      1+     rt    <A0L1N 


42 


THE    INFLUENCE   OF   FLUXES    AND   NON-FLUXES    UPON    THE    CHANGES 


ADDITION  OF  FLORIDA  KAOLIN. 

Shales.  The  first  addition  of  1%  of  kaoliu  to  Cauton 
shale  in  the  Cone  2  curve  produced  an  increase  in  porosity 
which  then  kept  practically  constant  until  6%  had  been 
added.  At  this  point  anotJier  slight  rise  in  [)orosity  took 
place.  Between  10  and  11%  a  sudden  drop  in  porosity 
was  observed,  and  it  is  evident  that  the  kaolin  in  this 
proportion  exerts  a  decided  fluxing-  action,  Fig.  27. 

In  the  Crawfordsville  shale  a  rise  in  porosity  at  2% 
and  a  drop  at  3%  is  observed.  With  15%  of  kaolin  a  very 
decided  decrease  in  porosity  is  noted  corresponding  to  the 
drop  with  11%  Canton  shale,  Fig.  28. 

In  the  Galesburg  shale  we  observe  (Cone  2  curve)  a 
drop  in  the  porosity  for  the  addition  of  1%  kaolin,  followed 
by  a  rise,  after  which  the  curve  has  a  slight  upward  slope. 
At  the  highest  percentage  of  kaolin  added,  15%,  the  mini- 
mum point,  if  tliere  is  one,  has  not  been  reached,  though 
the  curve  suggests  its  presence.  Fig.  29. 


TRAN5 

AM 

CER 

soc 

VOL  \ 

BLEININGE-K    AND  MOORE 

60 

CRAWFORDSVILLE    SHALE-KAOLIN 

50 

40 

/ 

^ 

y 

\ 

^^^ 

— — . 

^ 

Coi 

i.e( 

6^ 

^ 

->^ 

30 

^ 

■%, 

o 
0£ 

/ 

■> 

^> 

<^ 

"^ 

\ 

■^ 

// 

k 

1y 

r— ^ 

X 

P 

ne< 

^ 

\ 

o 

/ 

^ 

^ 

y 

J 

\ 

/ 

\ 

/ 

\ 

I 


KAOLIM    Z. 

+                6 

8 

10 

12. 

14 

15 

SHALE   96 

96             94- 
C  0  M  POSITION 

ga 

go 

88 

ee 

8i> 

IN    THE    POROSITY    AND    THE    SPECIFIC    GRAVITY    OF    SOME    CLAYS. 


43 


AXlS0>dOd% 


44        THE    INFLUENCE    OF    FLUXES    AND    NON -FLUXES    UPON    THE   CHANGES 

From  the  specific  gravity  and  porosity  curves  of  the 
single  Crawfordsville  shale  and  kaolin  mixtures,  Figs.  30 
and  31,  we  observe  several  interesting  phenomena.  The  1% 
mixture  curve  is  practically  parallel  to  the  pure  shale 
curve.     With  the  3%  mixture  the  kaolin  acts  as  a  flux 


TRANS. 

AM  CER    SOC    VOLX 

31EININGERAN0  MOORE 

FIG. 30. 

CRAWFORDSVltE  5H 
SPECIFIC  GRAVITY 

ALE- 
CU 

(AOUN 

^VES. 

Z.9 

2.7 

^ 

^ 

^^ 

:^=r- 

*^ 

J 

2.5 

\ 

=^ 

n 

r 

< 

a 

- 

o 

u. 

UJ 

- 

NO. 

l«  fi 

9% 

SHA 

Lt     l%K 

.AOLI 

N 

1.9 

..  5  .   95  ■•         "       5  • 
'+-   92  -          "        8  ■■ 

1.7 

•  5'   t 

8  - 

»      la    • 

03  06 

CONES 


between  Cones  09,  06,  and  03-2.  At  Cone  01  we  find  a 
distinct  minimum  point,  which  is  shown  also  in  the  5% 
mixture. 

The  Canton  shale-kaolin  mixtures  likewise  show  a 
minimum  point  at  Cone  01,  and  the  curves  indicate  that 
up  to  about  10%  the  clay  substance  does  not  exert  any 


I 


IN    THE    POROSITY    AND    THE    SPECIFIC    GR.'VVITV    OF    SOME    CLAYS. 


45 


tf 

■«- 

S:          a?  6?  0^  ^  55 
.     '              —   m   m   oQ    — 
M    U 
to    3J        uj 

0  5    ^  .  .  .   .  . 

I     *?  •^^  ?^  f  -  "^ 

P            0     W     ^     C^     —     ^ 
p-            0     OO     ^     Ol     CD     CD 

Z       

<           —    (VJ     rO     '4'     U^     « 

.^ 

^ 

^^ 

r^ 

/f 

=^ 

X 

rJ 

"-\ 

1      ^ 

^ 

^ 

/ 

S 

/ 

u 

-^ 

/ 

^ 

/ 

/ 

:^ 

^/ 

y 

<^ 

:^^ 

/>^ 

X 

0 

-*# 

^ 

j 

^o 

^ 

/ 

/ 

^ 

i^ 

^- 

— ■ 

J 

i^ 

>-- 

?? 

c 

> 

n"'4- 

*V»N  < 

3 

/> 

3 

in 

0 

0 

xiisoyoj  <'^ 


8 

FIG  31 

CRAWFGRDSVtLLE    SHALE -KAOLIN 
POROSITY. 

Z 

£ 

0 

z 

z 

<    ;    -    »    » 

I 

•^  .0  50  ,.    « 

0   a>   l^   «n   <vl 
0    ^    o>    O)   0^ 

t 

v 

■^rry 

\ 

/ 

/> 

\ 

/ 

;/ 

) 

0    0   0   0   0 
2  Z  Z  Z  Z 

i 

|/ 

A 

[^ 

f 

- 

-<^ 

?^ 

7^ 

'-^ 

* 

^ 

.^ 

:^ 

i^ 

> 
0 

^^ 

^ 

c 

ll 

// 

6^ 

JS^ 

5 

/ 

la 

z 

y^ 

r     1 

Y 

/ 

L 

Aiisoyod  % 


46        THE    INFLUENCE   OF   FLUXES    AND   NON-FLUXES    UPON    THE    CHANGES 

iufluence  upon  the  clay  below  Cone  03.  The  11  %  mixture, 
however,  shows  a  great  drop  in  porosity,  and  here  the 
kaolin  behaves  as  a  potent  flux.  Fig.  32.  The  fluxing  power 
of  kaolin  in  the  Galesburg  shale  is  shown  by  the  1%  curve, 
and  we  note  also  in  the  curves  up  to  8%  that  this  action 


TRANS.  AM  CER   SOC     VOL.X. 


BLEININGER  m  M03RE 


olO 


FIG. 33. 

GALESBURG  SHALE-KAOLIN 
POROSITY 

N0.1  -   100%  SHALE 

I'    99%      "      l^oKAOUN 
3  '    96  %     ')     4%     >> 
4-  «   94%    "      6%     a 

5  •    91  %     »      9  %      » 

!^ 

j. 

\ 

N, 

t 

^v 

\ 

k 

w 

\ 

V 

\ 

V 

\ 

'\ 

\ 

\ 

\ 

\\ 

N 

\ 

\ 

A 

■^ 

AJ 

^ 

\\ 

V 

N. 

\\ 

s. 

\ 

\ 

^. 

3 

X** 

"^ — 1 

^     - 

\ 

k^ 

^ 

^ 

4- 

i 

V 

i> 

— 

"v 

\ 

Z 

09  06 

CONES 


03 


takes  place  at  a  low  temperature,  between  Cones  09  and 
03,  the  rate  of  decrease  in  porosity  being  quite  steep. 

It  is  shown  clearly,  hence,  that  different  shales  react 
quite  differently  towards  kaolin,  and  it  is  not  at  all  im- 
probable that  this  might  afford  a  means  of  differentiation 
betAveen  the  structures  of  various  shales. 


IN    THE    POROSITY    AND    THE    SPECIFIC   GRAVITY    OF    SOME    CLAYS.  47 

ADDITION  OF  FELDSPAR-FLINT. 

Kaolin.  Mixtures  of  these  three  materials  offer 
special  interest  to  the  clay  worker  iiiasiiuich  as  they  make 
up  tlie  bulk  of  our  porcelain  bodies.  But  the  study  of  sudi 
a  system  becomes  more  complex,  and  hence  the  writers  have 
resorted  to  the  use  of  the  triaxial  diagram,  t\hich  is  a  well 
known   means  of  expressing  three  variable  compositions 


Tf^ANS.  AM    CER.   50C 

VOL.X-BlEininGER  and    MOORE. 

=  16.54-. 


with  the  constant  condition  that  the  sum  of  the  three  com- 
ponents be  equal  to  100.  The  use  of  the  triaxial  diagram 
has  been  explained  in  our  Transactions  by  ^Mr.  H.  E. 
Ashley  (Vol.  7).  To  recapitulate  briefly,  let  us  call  the 
lower  left  hand  corner  of  the  triangle,  Fig.  34,  the  origin 
or  0  per  cent  of  flint,  then  along  the  base  of  the  triangle 
we  measure  the  flint  so  that  the  right  hand  corner  stands 
for  lOO^f  of  flint.  Continuing  in  tlie  counter-clockwise 
direction  we  proceed  to  measure  the  feldspar  along  the 
right  side  of  the  triangle.    This,  of  course,  makes  the  100% 


48         THE    INFLUEN'CE    OF    FLUXES    AND    NON-FLUXES    ;;PON    THE    CHANGES 

tliiit  {'ornei'  equal  to  0^6  feldspar,  and  the  apex  of  the 
triangle  then  becomes  100%  feldspar  and  at  the  same  time 
0%  kaolin.  The  latter  thus  is  measured  along*  the  left  side 
of  the  triangle  and  the  lower  left  hand  corner  becomes 
equal  to  100%  kaolin.  We  might  thus  represent  to  our- 
selves the  diagram  nmde  up  of  three  triangles,  of  which  the 
apices  are  respectively  100%  flint,  100%  feldspar,  and 
100%  kaolin.  The  base  of  each  triangle  then  would  equal 
0%  of  flint,  feldspar  and  kaolin  respectively.  If  hence  we 
desire  to  plot  flint  we  would  measure  along  any  line  par- 
allel to  the  base  of  the  flint  triangle,  that  is,  parallel  to 
the  kaolin  line.  Similarly,  we  measure  feldspar  along  any 
line  parallel  to  the  base  of  the  feldspar  triangle,  that  is, 
parallel  to  the  flint  line.  The  kaolin  then  would  be  meas- 
ured along  lines  parallel  to  the  feldspar  line.  Thus,  a  mix- 
ture consisting  of  25-/(  flint,  25%  feldspar,  and  50% 
kaolin  would  be  measured  as  follows  (Fig.  34).  At  the 
point  25%  flint  we  follow  a  line  drawn  parallel  to  the 
kaolin  line.  We  then  proceed  to  the  feldspar  side  and  draw 
a  line  from  the  25%  point  parallel  to  the  flint  side.  The 
intersection  of  these  tAvo  lines  will  be  the  point  sought,  for 
on  draAving,  from  the  intersection  point,  a  line  parallel  to 
the  feldspar  side,  it  will  strike  the  kaolin  side  at  the  50% 
point.  The  point,  hence,  represents  25%  flint,  25^^.  feld- 
sj)ar,  and  50%  kaolin.  Similarly  anj'  other  mixture  may 
be  plotted. 

In  the  diagram  we  can  now  group  together  these  mix- 
tures, vitrifying  at  the  same  temperature  by  drawing  lines 
connecting  all  mixtures  whose  vitriflcation  point,  that  is, 
the  point  at  which  they  absorb,  not  more  than  I'yc  of  water 
is  the  same.  For  instance,  by  drawing  a  line  around  the 
area  including  all  mixtures  vitrifying  at  Cone  4  we  have 
defined  a  thermal  boundary,  and  the  resulting  curve  we 
call  the  isothermal.  By  doing  the  same  thing  for  the 
Cones  6  and  9  we  obtain  successive  areas  which  increase  in 
extent.  This  method,  therefore,  represents  not  only  the 
comijositions  which  may  be  expected  to  vitrify  at  a  certain 
temperature  from  which  the  one  most  suitable  for  prac- 


IN    THE    POROSITY    AND    THE    SPECIFIC    GRAVITY   OF    SOME    CLAYS.  49 


TRANS.  AM. 

VQL.X-  BLEININGER   AND  MOORE 


PIG. 35. 


FLA.  KAOLIN 


tical  operation  may  be  selected,  but  it  also  shows  distinctly 
the  intervals  between  the  isothernials,  thns  expressing  the 
range  of  the  vitrification  areas.  Fii>-.  35  thus  gives  us  a 
suniniary  of  the  vitrification  behavior  of  the  system  Flor- 
ida kaolin-flint-feldspar,  which  needs  no  further  explana- 
tion. 

In  Figs.  30,  37,  38,  39,  40,  41  we  have  mixtures  of  30%, 
40%,  50%,  G0%,  70%,  and  80%.-  of  Florida  kaolin.  In  all 
the  series  excepting  one,  the  40%  series,  the  porosity  curves 
are  fairly  smooth.  In  this  series  two  distinct  maximum 
points  are  observed;  one  with  lO'/c  flint  and  50%)  spar,  the 
other  with  50%  flint  and  10%  spar.  The  cause  of  these  two 
changes  the  writers  do  not  venture  to  explain.  In  regard  to 
the  individual  porosity'  curves  of  the  kaolin-feldspar-flint 
series  the  rate  of  decrease  in  porosity  becomes  very  sudden 
under  two  conditions,  viz.,  in  the  kaolin-feldspar  mixtures 
in  the  absence  of  flint,  and  in  the  mixtures  containing  but 
a  small  amount  of  flint  compared  with  the  amount  of  feld- 
spar.    This  is  more  pronounced  in  the  low  kaolin  series. 


50         THE   INFLUENCE   OF   FLUXES    AND   NON-FLUXES    UFON    THE    CHANGES 


TRANS  AM   CER.  SOC     VOL  X 


BUEININ&ER      AND      MOORE 


AC 


30 


=20 


F 

KA 
LIN 

FIG.3 

OLIN    = 
T  +  5P> 

5. 
30 

Z 
=  7C 

% 

-^ 

^ 

y 

_^ 

■-Cs 

ne 

B9_ 

;?^ 

fC 

.ej 

^ 

/^ 

/ 

\r 

^/ 

/ 

,^ 

/ 

\P> 

^ 

^-^ 

/ 

/^ 

y 

f, 

^/ 

/ 

— 

^" 

_x 

S!^^ 

ie2 

^ 

«^ 

^ 

-^ 

^ 

y 

FLINT    10 

20 

30 

40 

50 

60 

70 

SPAR    60 

50 

+0 

30 

Zt> 

10 

0 

TPvANS    AM     CER     SQC     VOL  X 


BLEININGER     AND   MOORE 


40 


30 


>- 


LlO 


1 

=LIJ 

PIC 
\OLI 

137 

N 
SP/ 

=  40 

% 
60 

'/., 

^ 

^ 

"^ 

^ 

■ 

cov 

\.eO 

5^ 

— 

=H 

>»,  ^ 

-^ 

' 

/ 

r 

\ 

/} 

A 

n 

V 

i 

1 

N 

^ 

I 

\ 

If 

> 

7 

\ 

rr^ 

// 

/^ 

j 

1 

^v^ 

'\ 

/■ 

/ 

// 

\\ 

^ 

5^ 

^. 

j 

' 

J 

\ 

1 

^ 

// 

\" 

-A 

*^ 

^ 

J^ 

f 

/ 

/ 

^ 

^^ 

J 

y 

\ 

sCo 

ne 

^ 



— 



^ 

FLINT       10  20  30 

SPAR       50  40  30 

C  OMPOSITION 


IN     THE    POROSITY    AND    THE    SPKCIKIC    GRAVITY    OK    SOME    CLAYS.  51 


TRANS 

AM   CER    SOC 

VOLX 

BLEININQER 

AND 

MOORE 

-. 

KA 
LIN 

FIC 

OLir 

IT  + 

.38 
SPA 

50% 
^R  - 

50 '/c 

40 

Co 

we 

06 

_,^ 

^X 

30 

■^^ 

-^ 

^ 

V 

'N 

L 

^ 

y 

/ 

r-''^ 

^ 

^ 

^ 

CO 

, 

c' 

^1 

,e^ 

P^ 

/ 

' 

— 

^ 

y 

if 

y 

y 

^ 

A 

^ 

*~-- 

V. 

^ 

FLINT  8  16 

SPAR         4-2  3+ 

C  OMPOSITION 


24 

32 

40 

48 

50 

26 

18 

10 

2 

0 

TRANS    AM   CER    SOC     VOL  X 


BLEININOER   ANO    MOORE 


FIG  39. 

KAOLIN   -  60% 
FLINT&SPAR-407o 


FLINT 
SPAK 


6 

12 

18 

24- 

30 

J4 

28 

COMPOSITION 

22 

16 

10 

36 

4 


40 
0 


52        THE    INFLUENCE   OF   FLUXES    AND    NON-FLUXES    UPON    THE    CHANGES 

TRANS     AM   CER  SOC.      VOL  X  BLEININGER    AND   MOORE 


FIG  4-0. 

KAOLIN       =70% 
FLINT&  SPAR  30% 


FLINT     4  8  12  16  20  2+  26 

SPAR   26  22  18  14  10  6  ^ 

COM  POSITION 


TRANS  AM  CER.  SOC 

VOLX 

BLEININGER 

AND 

MOORE 

FI&41 

i 

8( 

)7o  KAOLIN  -20%SPAR  +  FLINT 

■       1       ,                           11 

50' 

1      i 

'       i       1 

i 

i 

45 

i 

1       1       1       1 

i 

\ 

\~£Aj1&  06           1      ^ 

—^==tA 

35^  "•""'"'^ 

1 

1 

— 

^^ 

30 
^25 

' 

^^^ 

~"S~-^   Zo^-*^^'     '       j 

^ 

jT 

1 

1 

i 

vn         /, 

1        i 

1 

i 

s^°r 

\ 

1 

^ 

^ 

£l5 

/ 

^ 

^ 

/ 

/ 

X 

C  o'r^'S.i 

» 

^ 

10 

^ 

y 

r  n 

Tie 

4- 

\ 

5 



d 

H 

Nj 

^ 

FLINT  2 

+ 

6 

8 

10 

12 

14 

16 

18 

20 

SPAR    18 

16 

14 

IE 

PER 

10 

8 

6 

4 

2 

0 

IN    THE    POROSITY    AND    THE    SPECIFIC    GRAVITY    OF    SOME   CLAYS.  53 


K 

o 

I 

%■ 

-     r      . 

5       . 

to  zt:  i  „ 

« 

s 

\o 

in 

*^ 

< 

^ 

--^ 

-■^ 

/ 

^ 

/ 

9 

^ 

o 

/ 

/ 

/^ 

/" 

/ 

^ 

m 

/ 

/ 

/ 

K 

/ 

/ 

/ 

} 

/ 

^          •^«\Jf<>'t'«>Ot^ 

7 

f 

( 

/ 

/ 

> 

^ 

/ 

/ 

/ 

\ 
/ 

^ 

y 

^ 

b>^ 

X 

X 
> 

/ 

.<^ 

^ 

V- 

[1^ 

-T^ 

^ 

o 

o 

/ 

^j*" 

b 

^ 

:^ 

^ 

UJ 

/ 

/ 

i 

K 

^^' 

s 

/ 

1/j 

z 

\t\t 

%L 

AJ.I90yOd  % 


K 
o 

2 

C3 

U. 

i  i 

a     «/: 

=^     z 

-J 

o 
< 

o 

\rt 

-I- 

rO 

^<vl 

7- 

^ 

^ 

y^ 

/ 

^ 

^ 

Z 

/ 

^ 

/ 

/ 

/^ 

> 

/ 

/ 

/ 

cu 

/ 

/ 

/ 

V" 

^^ 

^ 

A 

/ 

/J 

\ 

\ 

1 

) 

/ 

/ 

/ 

y 

--- 

; 

/ 

y 

X 

,/] 

/ 

./ 

^ 

^ 

> 

/ 

/i 

^ 

r^ 

o     +     OO 

+ 

/ 

A 

^ 

^ 

t 

K 

/ 

/ 

^ 

Z 

C3   vo    fg   <o 
rj    —     — 

5 

/ 

( 

z 

,       ^       .      ^      = 

Z 

-      »      ■■     o 

1- 

* 

11 

c^    * 

'i  4 

■^  ^ 

? 

o  UJ 

Z 


'^'^'^"^ 


Aii?oy Od  % 


04         THE    INFLUENCE    OF    FLUXES    AND    NON-FLUXES    UPON    THE    CHANCES 


TRANS.  AM    CER   S0( 

..    VOLX. 

BLEININGER  AND  MOORE 

40 

z 

• 

FIG44. 

KAOLIN   50% 
FLINT+SPAR50% 
POROSITY. 

4        inn  o/.  1/ A ni  iM 

2  =      4-0  "^o  FLINT  -t-IO^/o  SPAR 

3  •     3a          '           -18 

\ 
35 

6 

5 

■ 

n:::;^ 

^^TN 

5 
6 

-      12           »          -38 

50% 

„ 



■-^^ 

^^x 

\ 

1 

30 

X^ 

^^ 

V 

y^ 

^ 

\ 

Xv 

N 

^ 

v^ 

. 

25 

N 

\ 

^ 

\ 

N. 

4 

\ 

\ 

\ 

2 

20 

\ 

\ 

< 

V 

\ 

V 

>- 

""^ 

H 
O 

I 

N 

k 

\ 

o|5 

DC 
o 

\ 

\ 

^ 

N. 

\ 

Q_ 

^JO 

\ 

V 

V 

^ 

^ 

\ 

\ 

\ 

H 

<s 

X 

\ 

\ 

A 

5 

K 

■^ 

6 

N 

5 

09  06 

CONES 


03  Ot 


IN    THE    POROSITY    AND    THE    SPKCIFIC    GRAVITY    OF    SOME    CLAYS.  -Ji) 

As  the  fliut  iucreases  the  curves  assume  a  gentle  slope.  Au 
illustratiou  of  this  behavior  is  shown  by  Figs.  42,  43,  44. 
It  is  also  an  interesting  fact  that  feldspar  behaves  as  a 
powerful  Hux  at  such  low  temperatures  as  Cones  OG  ami  03. 
The  writers  find  it  impossible  to  discuss  the  many  curves 
available  from  these  series  without  greatly  exceeding  the 
limits  of  this  paper.  One  more  fact  might  be  mentioned, 
however,  and  this  is  the  tendency  of  high  feldspar  mixtures 
to  become  vesicular,  even  before  total  vitrihcation  is 
reached,  thus  obscuring  the  real  changes  taking  place  in 
the  molecular  body  structure. 

^halc.  The  effect  of  a  feldspar-flint  mixture  may  be 
observed  in  Fig.  45,  where  we  have  76%  Canton  shale  and 
24%  of  feldspar  and  flint.  It  is  seen  that  even  a  mixture 
of  7%  of  spar  and  17%  of  flint  exerts  a  fluxing  action 
upon  the  shale. 

Similar  effects  are  observed  on  the  (lalesburg  and 
Crawfordsville  shales.  Fig.  46  shows  the  vitrification 
of  some  Canton  shale-spar-flint  mixtures  in  which  the  flux- 
ing effect  of  these  components  at  Cone  2  becomes  quite 
evident. 

ADDITION  OF  LIME  SILICA. 

Shales.  The  effect  of  lime-silica  upon  the  Galesburg 
and  Crawfordsville  shales  is  shown  in  Figs.  47  and  48.  A 
mixture  of  5%  whiting  and  15%  flint  has  evidently  lowered 
the  vitrification  point  of  the  Galesburg  shale  to  Cone  2 
and  that  of  the  Crawfordsville  shale  to  01.  In  each  case 
this  is  accomplished  at  the  sacrifice  of  the  safe  to  a  rapid 
rate  of  vitrification.  The  presence  of  the  silica  seen)s  to 
have  a  slight  modifying  effect  since  the  curves  are  not  so 
abrupt  as  they  would  be  if  the  lime  were  added  alone. 

In  Figs.  49,  50  and  50a  we  find  assembled  some  of  the 
vitrification  curves  of  these  shales  blended  with  varying 
amounts  of  flint  and  whiting. 


56        THE   INFLUENCE   OF   FLUXES    AND   NON-FLUXES    UPON    THE   CHANGES 


sC  CO 


1 


Xl*ISO^Od' 


IN    THE    POROSITY    AND    THE    SPECIFIC    GRAVITY    OF    SOME    CLAYS.  ")7 


TRANS   AM.  GER  SOC      VOL  X. 


BLEJNINGER   AND  MOORE 


40 


35 


30 


25 


ZO 


H|5 


10 


0^ 


FIG  4-6 

CANTON  SHALE-SPAR-FLINT 
POROSITY. 

NO  l')00  7o  SHALE 

2      76%         »       2^%SPAR     2.%FLINT 

3       »             ^^16          ''6            » 

5     "          »       e       ><      16         » 

J 

^^ 

1 

^ 

^ 

Ss 

^"^ 

\ 

\ 

^^ 

\ 

\ 

^ 

\\ 

\ 

\ 

t. 

y 

A 

\ 

\ 

1 

N 

A 

\ 

A 

^ 

W 

4 

\ 

V- 

--. 

S, 

\ 

ik 

^ 

% 

^^ 

6 

^ 

2 

b 

OS  06 

CONES 


03 


01 


58        THE    INFLUENXE    OF    FLUXES    AND   NON-FLUXES    UPON    THE   CHANGES 

TRANS.  AM.  CER,  SOC     VOLX  BLEININGER     AND  -MOORE 


CaCOj     3 

5 

7               9 

II 

13 

15 

17 

19 

FLINT  17 

15 

13              11 

COM  POSITION 

3 

7 

5 

i 

1 

TRANS.    AM    CER     SOC      VOLX 


BLEININGEf?     AND    MOORE 


FIG  4-8 

CRAWFOROSVILLE  SHALE  80% 
FLINT  8c  CaCO^  20% 


C01CO3     Z  4  6  8 

FLINT   la  16  14-  la 


I 


10  12  1+  16  18  i.Q 

10  9  6  4.  2  0 


IN    THE    POROSITY    AND   THE    SPECIFIC    GRAVITY    OF    SOME    CLAYS. 


59 


t= 

X 

=  ' 

- 

FIG  50. 

;rawfordsville  shale 

flint-whiting 

porosity. 

1  0-°  5S  # 

H^    iT)    ts.    cr> 

S  *9   0^   «^ 
t  \2  !2   — 

^    ,     .     .     = 

X 

■^                    0-9 

OO       "                  "      ° 
—     cj     rn     -»■     "O 

m 

m- 

l-ivi- 

- 

/ 

' 

/ 

^ 

y 

\ 

^ 

>^ 



■</ 

^ 

•^ 

^ 

-^ 

^ 

=- 

^ 

^ 

^ 

y 

-^ 

J^ 

-^ 

y 

^ 

^ 

/ 

/ 

J 

^ 

\ 

/ 

/ 

\ 

J 

\ 

/ 

-h 

s. 

/kiisoy  Od  % 


i 

5 

i 

UJ 

>3    3  To 

u.  cDi-a: 

.rtzo 

o 

vi   ^   o    ^    K 

i 

JO    ^    o    >o    rO 

UJ 

i  =  =  ^  -  § 

o 

^ 

in 

"/ 

^ 

^ 

^ 

-^ 

^-~ 

^ 

^^ 

^ 

—    i\j    m    ^    m 

>o 

/ 

/* 

"^ 

^ 

/ 

// 

^ 

=== 

X 

:> 

/ 

X 

^ 

^ 

:=^ 

H 

> 

// 

// 

^ 

V 

:^ 

o 

//I 

// 

•^ 

/ 

5 
< 

in 

1 

/ 

/ 

' 

/ 

1- 

/ 

\\ 

/ 

n 

4 

? 

in  <J, 

rf^- 

vO  c 

3 

n 

3 

n 

z> 

L 

r> 

A  i  I  s  0  y  0  d  °/o 


60        THE    IXFLUKNCE   OF    FLUXES    AND    NON-FLUXES    UPON    THE    CHANGES 


TRANS.    AM  CER.  SOC    VOLX 


BLEININGER  ANDMOORE 


4-0 


35 


30 


25 


20 


I/) 
o 

£•0 


3 

80 

FIG.SOa. 
%GALESBURG  SHALE 
FLINT-WHITING 
POROSITY 

Kin    4    ,(C<»/-CIIMX     CO/_\A/UlTIMr. 

> 

s. 

"""^ 

X 

2=11%    "       9%       » 

/ 

\ 

V- 

\ 

3  --  7%    "     13% 
'^-.  100%   SHALE 

\ 

\, 

^.^^  > 

^^ 

^ 

\ 

\, 

\ 

1 

^ 

\j 

\ 

\ 

\ 

1 

\ 

N 

\1 

V 

\ 

\ 

1 

k 

\ 

\ 

\ 

\ 

l\ 

^ 

\, 

\ 

\ 

A 

i 
4- 

2 

!3 

OS 


06  03 

CONES 


IN    THE    POROSITY    AND   THE    SPECIFIC    GRAVITY   OF    SOME    CLAYS.  61 

ADDITION   OF   FERKK"   OXIDE-FLINT. 

Shales.  Iii  Fig.  51,  sliowing  the  porosity  curves  of 
80%  Crawfordsville  shale  and  20%  ferric  oxide  and  flint, 
Ave  observe  at  once  that  the  reactions  appear  complex,  and 
by  no  means  continuous.  In  the  Cone  2  curve  we  have 
three  distinct  minimum  points.  We  also  observe  that  the 
reactions,  whatever  they  may  be,  begin  at  a  low  tempera- 
ture, since  the  curves  lie  very  close  together.  With  6^c 
FeoOg  even  the  Cone  01  curve  has  come  considerably  below 
tlie  porosity  shown  in  the  normal  shale  at  Cone  2.  We 
observe  in  this  connection  the  fact  that  at  Cone  01  the 
shale  shows  a  lower  porosity  than  at  Cone  2.  This  increase 
in  porosity  at  the  higher  temperature  appears  to  be  due  to 
vesicular  structure,  wliich  is  observed  eyen  before  vitrifica- 
tion is  reached  at  any  point.  With  16%  FeaO-.  the  shale 
mixture  reaches  complete  vitrification  at  Cone  2,  at  which 
temperature  the  normal  shale  has  a  porosity  of  11%. 

In  a  mixture  of  759^    Canton  shale  and  257^   ferric 


TRANS.  AM  CER    SOC     VOLX. 


BLEININGER   AND    MOORE 


*-0 


30 


»- 


FIG  51. 
CRAWFORDSVILLE  SHALE=807o 
FLINT+ Fez 03=20%  • 
POROSITY.- 


fctOj 

^ 

♦ 

6                8                10 

12 

14- 

16 

m 

20 

FLINT 

18 

16 

14              12                10 
%    COMPOSITION 

8 

6 

4 

2 

0 

62         THE    INFLUENCE    OF    FLUXES    AND    NON-FLUXES    UPON    THE    CHANGES 

oxide  and  flint,  Fif>-.  52,  we  observe  somewhat  similar  con- 
ditions. Complete  vitrification  is  reached  here  as  low  as 
Cone  01,  at  which  temperature  the  normal  shale  has  a 
porosity  of  12%.  This  point  occurs  with  a  mixture  of  10% 
FCoOg,  15%  flint,  that  is,  with  a  ratio  of  2 : 3. 

The  Galesburg'  shale  seems  to  behave  more  regularly 
than  the  preceding  clays,  and  does  not  appear  to  produce 
the  vesicular  structure  observed  in  the  former.  No  decided 
change  seems  to  take  place  at  Cone  2  for  the  changes  in  the 
iron-flint  ratio.  Fig.  -53. 

The  individual  vitrification  curves  of  these  shales- 
iron-flint  combinations  are  illustrated  in  Figs.  54,  55,  5(i. 

Similar  results  have  l>een  obtained  by  "\\'orcester  in 
experiments  involving  the  production  of  nuxtures  of  red 
Bedford  shale  and  ground  Berea  grit. 

ADDITION    OF   FERRIC   OXIDE-LIMB. 

Shales.  Here  we  observe  that  in  a  mixture  of  90% 
of  Crawfordsville  shale,  3%   FegOg  and  7%^  whiting  have 


TRANS.  AM  CER  SOC      VOLX. 


BLEININGER     AND    MDORE 


FIG  52. 
CANTON  SHALE  75% 
FLINT  +  FCsOa  25% 
POROSITY, 


IN    THE    POROSITY    AND    THK    SPECIFIC    GRAVITY    OF    SOME    CLAYS. 


03 


uJ 
O 
1 

z 

/ 

/ 

\ 

oc 

UJ 

/ 

/ 

z 
z 

UJ 

/ 

/ 

IC 

I 

( 

"-^  . 

\ 

\, 

\' 

\ 

\ 

LLI       ■• 

go- 

Fl 

01 

a  <J  4- 

1 

0 

u 

OQ    Z 
«/>    -. 

< 

/ 

i 

\ 

/ 

) 

/ 

>< 

C3 

/ 

/\ 

> 

y 

/ 

l\ 

[ 

O 

/ 

\ 

< 

in 

z 

\ 

1 

< 
I— 

CD  M 


>o  + 


OO^J, 


li 


-^^fi 


c? 


'  MSOyOd  % 


64 


THE    INFLUENCE    OF    FLUXES    AND   NON-FLUXES    UPON   THE    CH.\NGES 


FIG  55. 

CANTON  SHALE 

FLINT- Fe^Oa 

POROSITY. 

u. 

^ 

IM   -t    -^  «   - 

l- 

- 

fO 

H-)     —     (T.    N     .t 
< 

X 

?                    7 

^   fj    lO   ■*    lO    vD 
1 

\ 

M^^ 

./ 

in 

/ 

/  " 

> 

\ 

\ 

- 

<^ 

r 

/ 

/ 

) 

^ 

\ 

-^ 

z' 

/ 

yy 

^ 

/ 

) 

y 

^ 

i^ 

^ 

y 

y 

^ 

/ 

\ 

v-d 

/ 

/ 

/ 

^ 

/ 

r 

/ 

/ 

/ 

/ 

r 

y 

/■ 

J 

^ 

7 

^ 

4 

^ 

/, 

-^ 

=^ 

d 

^ 

AilSO«0d% 


"  c 

HI 

iii 

lu   o  >- 

-J        <M    f- 

d    «   — 
+  >"-</) 

3  2  t  c 

"■  g  i  o 

li.    _l    Q- 

< 

J    =       .       t 

s 

$  N  -  ? 

2        5         =          S 

u. 

°^    K>    CO    M 

- 

5 
a: 

i3 

rO 

+ 

rJj) 

^ 

<    .     ~    -     - 

X    -     "     -     - 

CO                           — 

\ 

/ 

; 

/ 

\ 

'/ 

/ 

^  isi  en  -"t 

2 

lO 

A 

^ 

7 

/' 

J^ 

/ 

Y) 

l/ 

/ 

> 

/ 

^ 

i 

/ 

/^ 

/ 

-^ 

^ 

'l-^ 

=7 

i^ 

i 

t 

^ 

r 

/ 

o 

^ 

/ 

^ 

J 

^ 

/ 

2 

*/ 

1. 

c 

z> 

-i 

c 

i> 

y 

r^ 

13 

Axisoyod  % 


IN    THE    POROSITY    AND    THE    SPECIFIC    GRAVITY    OF    SOME   CLAYS.  65 


TRAN5.  AM  CER   SOC    VOLX. 

BLEININGER    AND  MOORE 

FIG  56. 

GALESBURG    SHALE 
FLINT-FezOj 
POROSITY. 

N0.1.30%SHALE  I7%FUNT  3%Fe?0. 

2  '•           1+        "        6 

3  •>           10         "       10 

3 

4  "             6        "        14         -J 

5  '•            t        »       18 

\ 

b  •  IWOVo     " 

M 

^». 

Y 

\ 

N 

\i 

\0 

V 

\ 

V 

^\ 

s 

X 

\ 

.^ 

L 

\ 

^ 

1 

CI 

V- 

\ 

V 

A 

\ 

k 

\ 

v 

vN 

v 

4- 

A 

\ 

^ 

V 

^ 

s 

^ 

V 

•\ 

2) 

2. 

^ 

N 

5 
1 

08 

0 

6 

0 

b 

c 

1 

i 

> 

CONES 


66        THE   INFI.UENXE    OF    FLUXES    AND   NON-FLUXES    UPON    THE   CHANGES 

TRANS   AM    CER    i'OC     VOLX  BlEININGER     AND     MOORE 


FIG  57. 
CRAWFOFfOSVILLE  5HALE=90%. 
CaCOj  +  FeaOj-IO"'.- 
POROSITY. 

1 

III! 

I 

1 

30 

N. 

. 

V 

i 

"^ 

^^ 

-— 

1 

20 

K 

s. 

J" 

y 

' 

^ 

(\\ 

^ 

_^ 

— ■ 

-^ 

^^ 

, 

^^. 

^ 
■^ 

N, 

/ 

\ 

y 

/^ 

i  '^°^\       i 

V 

^ 

y 

CaCOj      9 


3  4-5 

7  6  5 

.C  OMPOSITION 


TRANS    AM    CER     50C    VOL  X. 

BlEININGER 

AND  MOaRE 

40 

FIG  58. 

GALESBURG  SHALE  =90%    ' 

CaCOi+Fe2.03-107« 

POROSITY, 

1       1        ,        1       1       .        ,        1 

1 

c 

5iae 

06 

30 

"^ 

i 

V 

UJ 

\ 

V. 

a:20 

(L 

/ 

"■^-^ 

■^ 

Wi 

N 

S^ 

10 

^ 

^' 

CJ 

^ 

7 

^ 

s 

^v 

^^ 

^.^ 

•"^ 

— ^ 

^ 

\ 

- 

^^ 

CaCO,      9 


3  4-5 

7  6  5 

%C  OM  PO  SITIOIH 


IN    THE    POROSITY    AND    THE    SPECIFIC    GRAVITY    OF    SOME    CLAYS. 


r.7 


I 

\ 

\ 

1 

1 

UJ 

o 

z 

/ 

/ 

\ 

/ 

,/ 

) 

/ 

y 

r 

) 

z 

/ 

y 

/ 

y 

/ 

03 

/ 

/ 

/ 

/ 

\ 

/ 

\ 

65       n 

) 

s 

iL  ^i  ^ 
-J    "^  1- 

/ 

' 

(J)     X         rJ    CO 

in   </)    c>   o 

i5    2    t    Q^        - 

2    O    0- 

<     c^ 

o 

c^ 

i 

^\ 

5 

4 

c 

\ 

>< 

i 

N 

N. 

\ 

> 

/ 

\ 

) 

\ 

o 

/ 

^ 

/ 

O 

2 
< 

7 

/ 

/ 

\ 

< 

a: 
1- 

/ 

"\ 

CO  C\l 


v©  "t 


^  ^ 


<\i  CO 


vO   + 


^^ 


All  SO  y  od  '=>/o 


68        THE    INFLUENCE   OF   FLUXES    AND    NON-FLUXES    UPON   THE   CHANGES 

brought  the  vitrification  down  to  Cone  01.  Increase  in 
ferric  oxide  causes  the  vitrification  point  to  rise  until  the 
mixture,  9%  FeoO-;  and  1%  whiting  is  reached,  where  we 
have  a  second  minimum  point.  The  Cone  01  and  Cone  2 
curves,  it  will  be  observed,  are  very  close  together.  Fig.  57. 

In  the  Galesburg  shale  conditions  appeal*  to  be  some- 
what different  and  we  have,  within  the  range  studied,  only 
one  minimum  point  which  is  close  to  6%  Fe203,  4%  whit- 
ing in  the  Cone  01  curve.  In  the  Cone  2  curve  it  has  ad- 
vanced to  7%  Fe203  and  S^c  whiting.  Fig.  58. 

The  Canton  shale  seems  to  be  more  sensitive  to  sucli 
j^dditions,  as  is  shoAvn  in  Fig.  59,  where  it  appears  that  the 
shale  has  been  rendered  vesicular  in  structure  at  Cone  2. 
It  is  especially  peculiar  that  this  should  be  the  case,  since 
Cone  01  does  not  seem  to  have  produced  vitrification.  It 
is  possible  that  the  vitrification  range  is  so  narrow  that  it 
was  missed  in  the  experiments.  Yet  this  seems  hardly 
probable.  The  natural  conclusion  would  be  that  the  for- 
mation of  ''blebs"  took  place  before  general  vitrification 
set  in. 

In  the  individual  curves  of  the  Crawfordsville  shale 
series,  Fig.  GO,  a  gradual  change  in  the  slope  of  the  curves 
is  noted,  which  tends  to  become  smaller  as  the  FeoOg  in- 
creases. With  the  increase  of  the  ferric  oxide  there  is  ob- 
served a  peculiar  retardation  between  Cones  06  and  03. 
indicating  perhaps  some  phenomena  taking  place  between 
the  lime  and  the  iron.  Of  course  it  is  impossible  to  deter- 
mine just  what  this  change  is. 

In  the  Galesburg  shale  series,  Fig.  61,  the  gradation 
OH  increasing  the  iron  is  smoother  and  not  marked  by  the 
retardation  noted  above,  excepting  perhaps  in  the  4% 
whiting,  6%  FeoO:^  curve. 

The  Canton  shale  series,  Fig.  62,  is  not  comparable 
with  the  two  preceding  series,  owing  to  the  fact  that  here 
we  have  but  80%  shale  with  20%  lime  and  iron  oxide. 
However,  some  facts  are  brought  out.  First  we  have  the 
change  in  slope  with  the  decrease  in  lime,  and  second,  we 
obserA-e  between  Cone  01  and  2  a  marked  increase  in  poros- 


IN    THE    POROSITY    AND   THE    SPIiClFIC    GRAVITY    OF    SOME    CLAYS. 


69 


1 

if 

1 

or 

S 

^      2    .  . .  = 

>0     ^     ^         o 

Ui 

a 

z 

z 

^ 

^•i 

j> 

tf> 

a 

y 

/ 

/I 

^ 

^ 

/ 

r 

4 

^ 

^ 

^     <J3     :^ 

iZ   5   o 

UJ 

-1 
< 

^ 

X 

^ 

^ 

^ 

>< 

^^ 

^ 

^ 

y 

/ 

/ 

1 

g 

^ 

^ 

^"^ 

V 

?^ 

/ 

j/ 

/ 

/ 

/ 

/ 

/^ 

/ 

/ 

y 

/ 

o 

1/ 

/ 

/ 

»* 

/^ 

< 

[ 

y 

^^ 

/ 

^ 

x^ 

< 

\ 

^ 

^ 

^ 

/> 

^ 

Aiisoyod  % 


^ 

_ , 

^    ■ 

o 

a: 
to 

C    o  o  oc 

IL   tJ   O 

o 

—  1M  -O   ^   vo  t,  to 

6 

S.  to  l^  -O  *  -^  fvl 

—  (vj  K)  +  in  ^  ^ 

CO 

>B 

r- 

*l*V-t 

/ 

/ 

^ 

^ 

^ 

/ 

^ 

j^ 

/^ 

CO 

<C 

,^ 

d 

■^ 

^ 

^ 

^ 

^ 

^ 

J^ 

^ 

^ 

^ 

^ 

==^ 

7^ 

/ 

z 

^ 

^ 

^ 

y 

\ 

X 

/ 

/ 

\ 

[/ 

\ 

y 

^/ 

/ 

/ 

X 

^ 

7 

V 

/ 

^ 

^ 

^ 

-^ 

1. 

n  "1 

r^ 

'*V"*^ 

tj 

, 

[^ 

13 

-. 

^ 

Ail9  0y  Od  "/o 


70        THE    INFLUENCE   OF    FLUXES    AND    NON-FLUXES    UPON    THE   CHANGES 


TRANS.  AM.  CER.  SOC 

-.    VOLX. 

BLEININGER  AND  MOORE 

45 

FIG62. 

80%  CANTON  SHALE 

POROSITY. 

NCI  =  16%CaC0,     4%Fe.O, 

z 

40 

4 

2 .  10        "10          ■> 
3  '  12        »            8 

^    .       O                .                       l-> 

^ 

z^ 

^ 

'^^ 

5« 
6  ' 

6         "            14          • 
2          "             18           < 

3 
35. 

z^**^ 

=" 

;<^ 

^ 

^ 

(   ' 

iOO*? 

-o  SHALE 

1 

\ 

M 

7 

30 

^ 

w 

IV 

\ 

S, 

\ 

\ 

V 

lb 

^ 

X, 

I 

A 

5,5 
3 

^ 

^ 

V 

/  # 

20 

>- 
h- 

o 

a: 

"^ 

\ 

N 

\ 

V 

\ 

■^ 

1 

i 

y 

1 

o 
0- 

0 

1 

^ 

>^ 

P 

^  ^ 

r 

5 

I 

/ 

6 

\ 

y 

09  06 

CONES 


03  01 


IJV    THE    POROSITY    ANU    THE    SPECIFIC    GRAVITY    OF    SOME    CLAYS.  (1 

ity  which  api)t'ars  in  cvciy  curve,  the  cause  of  which  must 
be  soujiht  iu  the  production  of  vesicular  structure.  It  is  pos- 
sible that  vitriticatiou  had  set  in  at  Coue  1,  in  which  case 
it  was  niis.sed,  since  no  burn  was  made  at  this  tenii)ei-ature. 

From  the  data  presented  in  this  paper  the  writers  be- 
lieve that  the  method  of  determining  the  rate  of  the 
porosity  changes  affords  a  practical  meaus  of  examining 
the  vitriticatiou  phenomeiui  not  only  of  natural  elays,  but 
also  of  body  mixtures.  The  porosity  method  is  essentially 
a  practical  one,  and  where  it  is  desirable  to  know  the  niolc- 
ciilar  changes,  either  physical  or  chemical,  taking  place,  it 
must  be  supplemented  by  specific  gravity  curves  represent- 
ing the  true  specific  gravities  as  determined  by  the  pycno- 
nieter,  under  the  special  precautions  advised  in  this  paper. 
Unless  these  determinations  are  made  with  great  care  they 
are  of  little  value,  since  the  changes  involved  are  frequentl\ 
only  of  small  magnitudes.  The  specific  gravity  curves 
eniplo3'ed  in  this  paper,  hence,  are  not  close  enough  to 
admit  of  exact  conclusions. 

From  the  scientific  standpoint,  therefore,  wherever 
the  discussion  of  the  molecular  structure  is  involved,  the 
true  specific  gravity  curves  are  the  main  criteria  of  these 
-changes.  At  the  same  time  it  must  be  remembered  that 
the  true  specific  gravity  is  in  itself  the  resultant  of  the 
physical  and  chemical  phenomena  clearly  indicated  in  the 
first  part  of  this  contribution,  and  cases  might  occur  where 
the  rate  change  becomes  zero,  owing  to  neutralizing  factors- 
These,  however,  seem  to  be  the  exception.  The  poi-osify 
curves  are  sul>ject  to  grave  errors  under  certain  conditions. 

The  maximum  or  minimum  points,  so  important  in  the 
stu«ly  of  all  fusion  phenomena,  niay  frequently  be  detected 
by  the  porosity  curves.  Their  determination  is  more  exact 
if  fixed  by  the  specific  gravity  curve,  since  practically  all 
physical  or  chemical  phenomena  are  accompanied  by  a 
change  in  specific  volume,  and  since  nearly  all  silicates 
(not  containing  any  borates)  on  the  application  of  heat,  as 
far  as  known,  increase  in  volume. 

The  use  of  reagents  such  as  have  been  employed  in  this 


72        THE   INFLUENCE   OF    FLUXES    AND   NON-FLUXES    UPON    THE   CHANGES 

paper  seems  to  the  writers  to  be  of  considerable  value  in 
bringing  out  and  studying  tlie  differences  in  the  chemical 
and  physical  structure  of  clays.  Different  clays  will  re- 
spond differently  to  the  same  reagent  under  the  same  heat 
treatment.  To  illustrate,  every  potter  knows  that  there  is 
a  great  difference  between  the  behavior  of  English  china 
clay  and  American  kaolins.  By  heating  each  of  these  clays 
with,  say,  a  mixture  of  20^  flint  and  15%  feldspar  to 
several  temperatures,  different  porosity  curves  Avill  be  ob- 
tained, showing  the  distinct  characteristi'"  of  each  type  of 
material.  It  goes  without  saying  that  the  reagent,  what- 
ever it  may  be,  must  be  kept  the  same,  both  as  to  composi- 
tion and  fineness,  just  as  the  cement  manufacturers  and 
testers  employ  a  standard  sand  for  their  purposes.  This 
would  mean  the  storing  of  a  considerable  amount  of  such 
a  material.  The  preparation  of  the  test  pieces  also  should 
be  done  under  uniform  conditions. 

Another  extremely  important  factor  is  the  heat  treat- 
ment, which  should  be  continued  long  enough  to  establish 
conditions  of  equilibrium  and  should  be  noted  as  closely  as 
possible  with  reference  to  cone  temperatures.  That  the 
heating  should  be  the  same  in  each  case  is  self-evident, 
since  we  know  that  we  are  dealing  with  incomplete  reac- 
tions which  differ  for  different  heat  treatments. 

In  this  connection  the  need  of  a  really  satisfactory 
small  laboratory  test  kiln  becomes  very  apparent,  and  this 
problem  awaits  solution. 

As  has  been  said  before,  for  practical  purposes  the 
porosity  curves  are  amply  sufficient. 

There  can  be  no  doubt  but  that  we  must  approach  the 
study  of  our  clay  bodies  and  mixtures  along  this  line,  and 
before  definite  laws  can  be  laid  down  a  great  deal  of  work 
must  yet  be  done.  This  field  has  been  barely  opened,  but 
it  is  hoped  that  the  function  of  the  several  substances  stud- 
ied will  be  indicated.  What  is  needed  most  is  the  study 
of  the  simpler  combinations. 

In  conclusion,  the  writers  wish  to  express  their  in- 
debtedness to  Professor  C.  W.  Rolfe  for  having  granted 


IN    THE    POROSITY    AND    THE    SPECIFIC    GRAVITY    OF    SOME    CLAYS.  73 

the  fiiiuls  and   facilities   necessary   for  caiiyin*^  out   this 
work. 

DISCUSSION.* 

.1//-.  I'linit/:  This  jtaper  cannot  be  discusserl  af  all 
a(le(|uately  because  of  the  mass  of  data  presented.  The 
curve  form  is  probably  the  most  lucid  wa\  of  preseiitiui;' 
data,  but  the  mass  of  data  is  so  confouudiuj::  that  you  oau 
not  e.xpect  one  to  follow  il  in  the  short  time  which  lias 
been  i»iven  it. 

There  were  a  few  points  thoug;h  that  I  noticed  as  lie 
went  along;  for  instance,  ])erhaps  that  iron  did  not  seem 
to  have  acted  as  a  flux,  as  we  supposed  it  did,  except  in  the 
role  of  a  catalyzer.  We  noted  the  same  thine:  last  year  in 
the  study  of  the  microsco])ic  sli<h's  of  burned  shales,  the 
iron  separated  out  into  definite  crystals  instead  of  com- 
bining with  the  silica.  If  iron  combines  with  silica  to  any 
great  extent  it  certainly  would  in  a  shale  burned  to  a  very 
dark  chocolate  color  under  both  reducing  conditions  and 
great  heat.  Under  ea<li  of  these  conditions  the  iron  sep- 
arated out  into  definite  crystals.  We  have  had  data  pre- 
sented here  today  showing  that  the  iron,  instead  of  fluxing 
the  clay,  seems  to  have  acted  as  a  refractory  agent,  prevent- 
ing the  closing  of  the  pores.  The  effect  of  iron  on  the 
specific  gi-avify  seems  to  be  that  to  some  extent,  it  holds 
it  nj),  if  if  does  not  iin-i'ease  if.  The  same  ju-oxcd  to  l»e 
tiMie  with  lime  in  lai-ge  (|uantity.  Lime  in  small  (pianfifi<'s 
fends  to  deci-ease  the  density  of  clay  by  fusion,  and  hence 
a  moleculai-  arrangement  of  the  fused  constituent,  and  also 
by  develojunenf  of  vesicular  structure,  but  in  excess  of 
seven  percent,  it  temls  to  increase  the  density  of  the  mass. 
This  is  new  to  me,  but  T  have  no  doubt  it  will  be  fruitful 
of  new  posfnlations  when  wo  como  to  study  the  curves. 

It  has  been  noted  that  sand  added  to  shale  increased 


*1  his  paper  was  not  read  nor  presented  in  its  entirety:  such  portion 
that  was  presented  was  given  e.xtemporaneously  by  Mr.  Moore.  Those 
whose  discussed  the  paper  have  not  had  opportunity  to  see  it  as  it  appears 
above. —  (Editor.) 


(4        THE    INFLUENCE   OF    FLUXES    AND    NON-FLUXES    UION    THE   CHANGES 

its  tou<];liuess  wheu  made  into  the  form  of  brick  and  used 
as  a  paver.  Sand}'  clays  are  as  a  rule  better  paving-  matei-- 
ials  than  those  containino-  no  sand ;  and  sand — not  pure 
quartz — added  to  clay  increases  its  toughness.  You  cannot, 
however,  add  lake  or  glass  sand  and  expect  this  constancy 
in  specific  gravity;  nor  can  you  expect  this  constancy  in  the 
porosity  changes  with  increasing  heat  treatment,  indicated 
by  the  curves  just  shown  to  us.  Von  must  have  sand  which 
is  more  or  less  combined,  more  or  less  in  solid  solution,  as 
the  chemists  say,  in  order  to  have  this  steadiness  of  be- 
havior in  regard  to  fusion.  The  behavior  of  silica  in  de- 
creasing the  specific  gravity  without  causing  definite  flux- 
ing action  is  interesting.  When  a  quartz  crystal  expands 
on  heating  it  breaks,  molecularly,  and,  at  the  same  time, 
the  molecules  increase  in  volume.  Notwithstanding  the 
increased  contact  surface  that  follows  as  a  consequence  of 
this  increase  in  volume,  silica  did  not  appear,  in  these  ex- 
periments, to  act  as  a  flux. 

I  noticed  that  Cone  2  seemed  to  be  the  critical  point 
in  all  mixtures,  the  point  at  which  fusion  begins  to  progress 
most  rapidly.  So  Cones  2  and  3  can  be  said  to  be  quite 
critical  temperatures  for  most  clays,  if  not  for  all  clays 
and  mixtures. 

The  behavior  of  kaolin  when  added  to  shale  is  most 
interesting.  It  seems  to  cause  a  fluxing  action  in  small 
amounts  and  a  refractory  action  in  lai'ger  amounts.  What 
is  a  flux?  We  have  been  used  to  classifying  the  bases,  lime, 
magnesia,  etc.,  as  fluxes.  We  classify  Cornwall  stone  and 
feldspar  as  fluxes,  and  clay  and  sand  as  refractories.  We 
have  an  instance  here  of  clay,  a  very  refractory  material, 
acting  as  a  flux  Avhen  mixed  with  shale.  How  can  we 
harmonize  this  with  our  definition  of  a  flux?  It  seems  we 
ought  to  have  a  different  definition  from  that  we  have  been 
using. 


r ^.:.i  ■■if;         *, 


^^^..^ 


UNIVERSITY  OF  ILLIN0I9-URBANA 


I 3  0112  052567101 

t2 


vyX 


.^-^vfi-A' 


